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authorRincewindsHat <12514511+RincewindsHat@users.noreply.github.com>2021-12-02 14:11:21 (GMT)
committerGitHub <noreply@github.com>2021-12-02 14:11:21 (GMT)
commitdf1e9e975f69c8f7965bab91684870fe509739c6 (patch)
tree526b0c77c524b2219d5a48fd78b8302f055a4a5b /tools
parent6246b8f1830e8a375bc656deafd28aab715b4fd9 (diff)
parent1a3a715702a5b6709fed2a1eb53ec644c9968057 (diff)
downloadmonitoring-plugins-df1e9e975f69c8f7965bab91684870fe509739c6.tar.gz
Merge branch 'master' into mailq-add-config-dir
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1# WELCOME TO SQUID 3.5.27
2# ----------------------------
3#
4# This is the documentation for the Squid configuration file.
5# This documentation can also be found online at:
6# http://www.squid-cache.org/Doc/config/
7#
8# You may wish to look at the Squid home page and wiki for the
9# FAQ and other documentation:
10# http://www.squid-cache.org/
11# http://wiki.squid-cache.org/SquidFaq
12# http://wiki.squid-cache.org/ConfigExamples
13#
14# This documentation shows what the defaults for various directives
15# happen to be. If you don't need to change the default, you should
16# leave the line out of your squid.conf in most cases.
17#
18# In some cases "none" refers to no default setting at all,
19# while in other cases it refers to the value of the option
20# - the comments for that keyword indicate if this is the case.
21#
22
23# Configuration options can be included using the "include" directive.
24# Include takes a list of files to include. Quoting and wildcards are
25# supported.
26#
27# For example,
28#
29# include /path/to/included/file/squid.acl.config
30#
31# Includes can be nested up to a hard-coded depth of 16 levels.
32# This arbitrary restriction is to prevent recursive include references
33# from causing Squid entering an infinite loop whilst trying to load
34# configuration files.
35#
36# Values with byte units
37#
38# Squid accepts size units on some size related directives. All
39# such directives are documented with a default value displaying
40# a unit.
41#
42# Units accepted by Squid are:
43# bytes - byte
44# KB - Kilobyte (1024 bytes)
45# MB - Megabyte
46# GB - Gigabyte
47#
48# Values with spaces, quotes, and other special characters
49#
50# Squid supports directive parameters with spaces, quotes, and other
51# special characters. Surround such parameters with "double quotes". Use
52# the configuration_includes_quoted_values directive to enable or
53# disable that support.
54#
55# Squid supports reading configuration option parameters from external
56# files using the syntax:
57# parameters("/path/filename")
58# For example:
59# acl whitelist dstdomain parameters("/etc/squid/whitelist.txt")
60#
61# Conditional configuration
62#
63# If-statements can be used to make configuration directives
64# depend on conditions:
65#
66# if <CONDITION>
67# ... regular configuration directives ...
68# [else
69# ... regular configuration directives ...]
70# endif
71#
72# The else part is optional. The keywords "if", "else", and "endif"
73# must be typed on their own lines, as if they were regular
74# configuration directives.
75#
76# NOTE: An else-if condition is not supported.
77#
78# These individual conditions types are supported:
79#
80# true
81# Always evaluates to true.
82# false
83# Always evaluates to false.
84# <integer> = <integer>
85# Equality comparison of two integer numbers.
86#
87#
88# SMP-Related Macros
89#
90# The following SMP-related preprocessor macros can be used.
91#
92# ${process_name} expands to the current Squid process "name"
93# (e.g., squid1, squid2, or cache1).
94#
95# ${process_number} expands to the current Squid process
96# identifier, which is an integer number (e.g., 1, 2, 3) unique
97# across all Squid processes of the current service instance.
98#
99# ${service_name} expands into the current Squid service instance
100# name identifier which is provided by -n on the command line.
101#
102
103# TAG: broken_vary_encoding
104# This option is not yet supported by Squid-3.
105#Default:
106# none
107
108# TAG: cache_vary
109# This option is not yet supported by Squid-3.
110#Default:
111# none
112
113# TAG: error_map
114# This option is not yet supported by Squid-3.
115#Default:
116# none
117
118# TAG: external_refresh_check
119# This option is not yet supported by Squid-3.
120#Default:
121# none
122
123# TAG: location_rewrite_program
124# This option is not yet supported by Squid-3.
125#Default:
126# none
127
128# TAG: refresh_stale_hit
129# This option is not yet supported by Squid-3.
130#Default:
131# none
132
133# TAG: hierarchy_stoplist
134# Remove this line. Use always_direct or cache_peer_access ACLs instead if you need to prevent cache_peer use.
135#Default:
136# none
137
138# TAG: log_access
139# Remove this line. Use acls with access_log directives to control access logging
140#Default:
141# none
142
143# TAG: log_icap
144# Remove this line. Use acls with icap_log directives to control icap logging
145#Default:
146# none
147
148# TAG: ignore_ims_on_miss
149# Remove this line. The HTTP/1.1 feature is now configured by 'cache_miss_revalidate'.
150#Default:
151# none
152
153# TAG: chunked_request_body_max_size
154# Remove this line. Squid is now HTTP/1.1 compliant.
155#Default:
156# none
157
158# TAG: dns_v4_fallback
159# Remove this line. Squid performs a 'Happy Eyeballs' algorithm, the 'fallback' algorithm is no longer relevant.
160#Default:
161# none
162
163# TAG: emulate_httpd_log
164# Replace this with an access_log directive using the format 'common' or 'combined'.
165#Default:
166# none
167
168# TAG: forward_log
169# Use a regular access.log with ACL limiting it to MISS events.
170#Default:
171# none
172
173# TAG: ftp_list_width
174# Remove this line. Configure FTP page display using the CSS controls in errorpages.css instead.
175#Default:
176# none
177
178# TAG: ignore_expect_100
179# Remove this line. The HTTP/1.1 feature is now fully supported by default.
180#Default:
181# none
182
183# TAG: log_fqdn
184# Remove this option from your config. To log FQDN use %>A in the log format.
185#Default:
186# none
187
188# TAG: log_ip_on_direct
189# Remove this option from your config. To log server or peer names use %<A in the log format.
190#Default:
191# none
192
193# TAG: maximum_single_addr_tries
194# Replaced by connect_retries. The behaviour has changed, please read the documentation before altering.
195#Default:
196# none
197
198# TAG: referer_log
199# Replace this with an access_log directive using the format 'referrer'.
200#Default:
201# none
202
203# TAG: update_headers
204# Remove this line. The feature is supported by default in storage types where update is implemented.
205#Default:
206# none
207
208# TAG: url_rewrite_concurrency
209# Remove this line. Set the 'concurrency=' option of url_rewrite_children instead.
210#Default:
211# none
212
213# TAG: useragent_log
214# Replace this with an access_log directive using the format 'useragent'.
215#Default:
216# none
217
218# TAG: dns_testnames
219# Remove this line. DNS is no longer tested on startup.
220#Default:
221# none
222
223# TAG: extension_methods
224# Remove this line. All valid methods for HTTP are accepted by default.
225#Default:
226# none
227
228# TAG: zero_buffers
229#Default:
230# none
231
232# TAG: incoming_rate
233#Default:
234# none
235
236# TAG: server_http11
237# Remove this line. HTTP/1.1 is supported by default.
238#Default:
239# none
240
241# TAG: upgrade_http0.9
242# Remove this line. ICY/1.0 streaming protocol is supported by default.
243#Default:
244# none
245
246# TAG: zph_local
247# Alter these entries. Use the qos_flows directive instead.
248#Default:
249# none
250
251# TAG: header_access
252# Since squid-3.0 replace with request_header_access or reply_header_access
253# depending on whether you wish to match client requests or server replies.
254#Default:
255# none
256
257# TAG: httpd_accel_no_pmtu_disc
258# Since squid-3.0 use the 'disable-pmtu-discovery' flag on http_port instead.
259#Default:
260# none
261
262# TAG: wais_relay_host
263# Replace this line with 'cache_peer' configuration.
264#Default:
265# none
266
267# TAG: wais_relay_port
268# Replace this line with 'cache_peer' configuration.
269#Default:
270# none
271
272# OPTIONS FOR SMP
273# -----------------------------------------------------------------------------
274
275# TAG: workers
276# Number of main Squid processes or "workers" to fork and maintain.
277# 0: "no daemon" mode, like running "squid -N ..."
278# 1: "no SMP" mode, start one main Squid process daemon (default)
279# N: start N main Squid process daemons (i.e., SMP mode)
280#
281# In SMP mode, each worker does nearly all what a single Squid daemon
282# does (e.g., listen on http_port and forward HTTP requests).
283#Default:
284# SMP support disabled.
285
286# TAG: cpu_affinity_map
287# Usage: cpu_affinity_map process_numbers=P1,P2,... cores=C1,C2,...
288#
289# Sets 1:1 mapping between Squid processes and CPU cores. For example,
290#
291# cpu_affinity_map process_numbers=1,2,3,4 cores=1,3,5,7
292#
293# affects processes 1 through 4 only and places them on the first
294# four even cores, starting with core #1.
295#
296# CPU cores are numbered starting from 1. Requires support for
297# sched_getaffinity(2) and sched_setaffinity(2) system calls.
298#
299# Multiple cpu_affinity_map options are merged.
300#
301# See also: workers
302#Default:
303# Let operating system decide.
304
305# OPTIONS FOR AUTHENTICATION
306# -----------------------------------------------------------------------------
307
308# TAG: auth_param
309# This is used to define parameters for the various authentication
310# schemes supported by Squid.
311#
312# format: auth_param scheme parameter [setting]
313#
314# The order in which authentication schemes are presented to the client is
315# dependent on the order the scheme first appears in config file. IE
316# has a bug (it's not RFC 2617 compliant) in that it will use the basic
317# scheme if basic is the first entry presented, even if more secure
318# schemes are presented. For now use the order in the recommended
319# settings section below. If other browsers have difficulties (don't
320# recognize the schemes offered even if you are using basic) either
321# put basic first, or disable the other schemes (by commenting out their
322# program entry).
323#
324# Once an authentication scheme is fully configured, it can only be
325# shutdown by shutting squid down and restarting. Changes can be made on
326# the fly and activated with a reconfigure. I.E. You can change to a
327# different helper, but not unconfigure the helper completely.
328#
329# Please note that while this directive defines how Squid processes
330# authentication it does not automatically activate authentication.
331# To use authentication you must in addition make use of ACLs based
332# on login name in http_access (proxy_auth, proxy_auth_regex or
333# external with %LOGIN used in the format tag). The browser will be
334# challenged for authentication on the first such acl encountered
335# in http_access processing and will also be re-challenged for new
336# login credentials if the request is being denied by a proxy_auth
337# type acl.
338#
339# WARNING: authentication can't be used in a transparently intercepting
340# proxy as the client then thinks it is talking to an origin server and
341# not the proxy. This is a limitation of bending the TCP/IP protocol to
342# transparently intercepting port 80, not a limitation in Squid.
343# Ports flagged 'transparent', 'intercept', or 'tproxy' have
344# authentication disabled.
345#
346# === Parameters common to all schemes. ===
347#
348# "program" cmdline
349# Specifies the command for the external authenticator.
350#
351# By default, each authentication scheme is not used unless a
352# program is specified.
353#
354# See http://wiki.squid-cache.org/Features/AddonHelpers for
355# more details on helper operations and creating your own.
356#
357# "key_extras" format
358# Specifies a string to be append to request line format for
359# the authentication helper. "Quoted" format values may contain
360# spaces and logformat %macros. In theory, any logformat %macro
361# can be used. In practice, a %macro expands as a dash (-) if
362# the helper request is sent before the required macro
363# information is available to Squid.
364#
365# By default, Squid uses request formats provided in
366# scheme-specific examples below (search for %credentials).
367#
368# The expanded key_extras value is added to the Squid credentials
369# cache and, hence, will affect authentication. It can be used to
370# autenticate different users with identical user names (e.g.,
371# when user authentication depends on http_port).
372#
373# Avoid adding frequently changing information to key_extras. For
374# example, if you add user source IP, and it changes frequently
375# in your environment, then max_user_ip ACL is going to treat
376# every user+IP combination as a unique "user", breaking the ACL
377# and wasting a lot of memory on those user records. It will also
378# force users to authenticate from scratch whenever their IP
379# changes.
380#
381# "realm" string
382# Specifies the protection scope (aka realm name) which is to be
383# reported to the client for the authentication scheme. It is
384# commonly part of the text the user will see when prompted for
385# their username and password.
386#
387# For Basic the default is "Squid proxy-caching web server".
388# For Digest there is no default, this parameter is mandatory.
389# For NTLM and Negotiate this parameter is ignored.
390#
391# "children" numberofchildren [startup=N] [idle=N] [concurrency=N]
392#
393# The maximum number of authenticator processes to spawn. If
394# you start too few Squid will have to wait for them to process
395# a backlog of credential verifications, slowing it down. When
396# password verifications are done via a (slow) network you are
397# likely to need lots of authenticator processes.
398#
399# The startup= and idle= options permit some skew in the exact
400# amount run. A minimum of startup=N will begin during startup
401# and reconfigure. Squid will start more in groups of up to
402# idle=N in an attempt to meet traffic needs and to keep idle=N
403# free above those traffic needs up to the maximum.
404#
405# The concurrency= option sets the number of concurrent requests
406# the helper can process. The default of 0 is used for helpers
407# who only supports one request at a time. Setting this to a
408# number greater than 0 changes the protocol used to include a
409# channel ID field first on the request/response line, allowing
410# multiple requests to be sent to the same helper in parallel
411# without waiting for the response.
412#
413# Concurrency must not be set unless it's known the helper
414# supports the input format with channel-ID fields.
415#
416# NOTE: NTLM and Negotiate schemes do not support concurrency
417# in the Squid code module even though some helpers can.
418#
419#
420#
421# === Example Configuration ===
422#
423# This configuration displays the recommended authentication scheme
424# order from most to least secure with recommended minimum configuration
425# settings for each scheme:
426#
427##auth_param negotiate program <uncomment and complete this line to activate>
428##auth_param negotiate children 20 startup=0 idle=1
429##auth_param negotiate keep_alive on
430##
431##auth_param digest program <uncomment and complete this line to activate>
432##auth_param digest children 20 startup=0 idle=1
433##auth_param digest realm Squid proxy-caching web server
434##auth_param digest nonce_garbage_interval 5 minutes
435##auth_param digest nonce_max_duration 30 minutes
436##auth_param digest nonce_max_count 50
437##
438##auth_param ntlm program <uncomment and complete this line to activate>
439##auth_param ntlm children 20 startup=0 idle=1
440##auth_param ntlm keep_alive on
441##
442##auth_param basic program <uncomment and complete this line>
443##auth_param basic children 5 startup=5 idle=1
444##auth_param basic realm Squid proxy-caching web server
445##auth_param basic credentialsttl 2 hours
446#Default:
447# none
448
449# TAG: authenticate_cache_garbage_interval
450# The time period between garbage collection across the username cache.
451# This is a trade-off between memory utilization (long intervals - say
452# 2 days) and CPU (short intervals - say 1 minute). Only change if you
453# have good reason to.
454#Default:
455# authenticate_cache_garbage_interval 1 hour
456
457# TAG: authenticate_ttl
458# The time a user & their credentials stay in the logged in
459# user cache since their last request. When the garbage
460# interval passes, all user credentials that have passed their
461# TTL are removed from memory.
462#Default:
463# authenticate_ttl 1 hour
464
465# TAG: authenticate_ip_ttl
466# If you use proxy authentication and the 'max_user_ip' ACL,
467# this directive controls how long Squid remembers the IP
468# addresses associated with each user. Use a small value
469# (e.g., 60 seconds) if your users might change addresses
470# quickly, as is the case with dialup. You might be safe
471# using a larger value (e.g., 2 hours) in a corporate LAN
472# environment with relatively static address assignments.
473#Default:
474# authenticate_ip_ttl 1 second
475
476# ACCESS CONTROLS
477# -----------------------------------------------------------------------------
478
479# TAG: external_acl_type
480# This option defines external acl classes using a helper program
481# to look up the status
482#
483# external_acl_type name [options] FORMAT.. /path/to/helper [helper arguments..]
484#
485# Options:
486#
487# ttl=n TTL in seconds for cached results (defaults to 3600
488# for 1 hour)
489#
490# negative_ttl=n
491# TTL for cached negative lookups (default same
492# as ttl)
493#
494# grace=n Percentage remaining of TTL where a refresh of a
495# cached entry should be initiated without needing to
496# wait for a new reply. (default is for no grace period)
497#
498# cache=n The maximum number of entries in the result cache. The
499# default limit is 262144 entries. Each cache entry usually
500# consumes at least 256 bytes. Squid currently does not remove
501# expired cache entries until the limit is reached, so a proxy
502# will sooner or later reach the limit. The expanded FORMAT
503# value is used as the cache key, so if the details in FORMAT
504# are highly variable, a larger cache may be needed to produce
505# reduction in helper load.
506#
507# children-max=n
508# Maximum number of acl helper processes spawned to service
509# external acl lookups of this type. (default 5)
510#
511# children-startup=n
512# Minimum number of acl helper processes to spawn during
513# startup and reconfigure to service external acl lookups
514# of this type. (default 0)
515#
516# children-idle=n
517# Number of acl helper processes to keep ahead of traffic
518# loads. Squid will spawn this many at once whenever load
519# rises above the capabilities of existing processes.
520# Up to the value of children-max. (default 1)
521#
522# concurrency=n concurrency level per process. Only used with helpers
523# capable of processing more than one query at a time.
524#
525# protocol=2.5 Compatibility mode for Squid-2.5 external acl helpers.
526#
527# ipv4 / ipv6 IP protocol used to communicate with this helper.
528# The default is to auto-detect IPv6 and use it when available.
529#
530#
531# FORMAT specifications
532#
533# %LOGIN Authenticated user login name
534# %un A user name. Expands to the first available name
535# from the following list of information sources:
536# - authenticated user name, like %ul or %LOGIN
537# - user name sent by an external ACL, like %EXT_USER
538# - SSL client name, like %us in logformat
539# - ident user name, like %ui in logformat
540# %EXT_USER Username from previous external acl
541# %EXT_LOG Log details from previous external acl
542# %EXT_TAG Tag from previous external acl
543# %IDENT Ident user name
544# %SRC Client IP
545# %SRCPORT Client source port
546# %URI Requested URI
547# %DST Requested host
548# %PROTO Requested URL scheme
549# %PORT Requested port
550# %PATH Requested URL path
551# %METHOD Request method
552# %MYADDR Squid interface address
553# %MYPORT Squid http_port number
554# %PATH Requested URL-path (including query-string if any)
555# %USER_CERT SSL User certificate in PEM format
556# %USER_CERTCHAIN SSL User certificate chain in PEM format
557# %USER_CERT_xx SSL User certificate subject attribute xx
558# %USER_CA_CERT_xx SSL User certificate issuer attribute xx
559# %ssl::>sni SSL client SNI sent to Squid
560# %ssl::<cert_subject SSL server certificate DN
561# %ssl::<cert_issuer SSL server certificate issuer DN
562#
563# %>{Header} HTTP request header "Header"
564# %>{Hdr:member}
565# HTTP request header "Hdr" list member "member"
566# %>{Hdr:;member}
567# HTTP request header list member using ; as
568# list separator. ; can be any non-alphanumeric
569# character.
570#
571# %<{Header} HTTP reply header "Header"
572# %<{Hdr:member}
573# HTTP reply header "Hdr" list member "member"
574# %<{Hdr:;member}
575# HTTP reply header list member using ; as
576# list separator. ; can be any non-alphanumeric
577# character.
578#
579# %ACL The name of the ACL being tested.
580# %DATA The ACL arguments. If not used then any arguments
581# is automatically added at the end of the line
582# sent to the helper.
583# NOTE: this will encode the arguments as one token,
584# whereas the default will pass each separately.
585#
586# %% The percent sign. Useful for helpers which need
587# an unchanging input format.
588#
589#
590# General request syntax:
591#
592# [channel-ID] FORMAT-values [acl-values ...]
593#
594#
595# FORMAT-values consists of transaction details expanded with
596# whitespace separation per the config file FORMAT specification
597# using the FORMAT macros listed above.
598#
599# acl-values consists of any string specified in the referencing
600# config 'acl ... external' line. see the "acl external" directive.
601#
602# Request values sent to the helper are URL escaped to protect
603# each value in requests against whitespaces.
604#
605# If using protocol=2.5 then the request sent to the helper is not
606# URL escaped to protect against whitespace.
607#
608# NOTE: protocol=3.0 is deprecated as no longer necessary.
609#
610# When using the concurrency= option the protocol is changed by
611# introducing a query channel tag in front of the request/response.
612# The query channel tag is a number between 0 and concurrency-1.
613# This value must be echoed back unchanged to Squid as the first part
614# of the response relating to its request.
615#
616#
617# The helper receives lines expanded per the above format specification
618# and for each input line returns 1 line starting with OK/ERR/BH result
619# code and optionally followed by additional keywords with more details.
620#
621#
622# General result syntax:
623#
624# [channel-ID] result keyword=value ...
625#
626# Result consists of one of the codes:
627#
628# OK
629# the ACL test produced a match.
630#
631# ERR
632# the ACL test does not produce a match.
633#
634# BH
635# An internal error occurred in the helper, preventing
636# a result being identified.
637#
638# The meaning of 'a match' is determined by your squid.conf
639# access control configuration. See the Squid wiki for details.
640#
641# Defined keywords:
642#
643# user= The users name (login)
644#
645# password= The users password (for login= cache_peer option)
646#
647# message= Message describing the reason for this response.
648# Available as %o in error pages.
649# Useful on (ERR and BH results).
650#
651# tag= Apply a tag to a request. Only sets a tag once,
652# does not alter existing tags.
653#
654# log= String to be logged in access.log. Available as
655# %ea in logformat specifications.
656#
657# clt_conn_tag= Associates a TAG with the client TCP connection.
658# Please see url_rewrite_program related documentation
659# for this kv-pair.
660#
661# Any keywords may be sent on any response whether OK, ERR or BH.
662#
663# All response keyword values need to be a single token with URL
664# escaping, or enclosed in double quotes (") and escaped using \ on
665# any double quotes or \ characters within the value. The wrapping
666# double quotes are removed before the value is interpreted by Squid.
667# \r and \n are also replace by CR and LF.
668#
669# Some example key values:
670#
671# user=John%20Smith
672# user="John Smith"
673# user="J. \"Bob\" Smith"
674#Default:
675# none
676
677# TAG: acl
678# Defining an Access List
679#
680# Every access list definition must begin with an aclname and acltype,
681# followed by either type-specific arguments or a quoted filename that
682# they are read from.
683#
684# acl aclname acltype argument ...
685# acl aclname acltype "file" ...
686#
687# When using "file", the file should contain one item per line.
688#
689# Some acl types supports options which changes their default behaviour.
690# The available options are:
691#
692# -i,+i By default, regular expressions are CASE-SENSITIVE. To make them
693# case-insensitive, use the -i option. To return case-sensitive
694# use the +i option between patterns, or make a new ACL line
695# without -i.
696#
697# -n Disable lookups and address type conversions. If lookup or
698# conversion is required because the parameter type (IP or
699# domain name) does not match the message address type (domain
700# name or IP), then the ACL would immediately declare a mismatch
701# without any warnings or lookups.
702#
703# -- Used to stop processing all options, in the case the first acl
704# value has '-' character as first character (for example the '-'
705# is a valid domain name)
706#
707# Some acl types require suspending the current request in order
708# to access some external data source.
709# Those which do are marked with the tag [slow], those which
710# don't are marked as [fast].
711# See http://wiki.squid-cache.org/SquidFaq/SquidAcl
712# for further information
713#
714# ***** ACL TYPES AVAILABLE *****
715#
716# acl aclname src ip-address/mask ... # clients IP address [fast]
717# acl aclname src addr1-addr2/mask ... # range of addresses [fast]
718# acl aclname dst [-n] ip-address/mask ... # URL host's IP address [slow]
719# acl aclname localip ip-address/mask ... # IP address the client connected to [fast]
720#
721# acl aclname arp mac-address ... (xx:xx:xx:xx:xx:xx notation)
722# # [fast]
723# # The 'arp' ACL code is not portable to all operating systems.
724# # It works on Linux, Solaris, Windows, FreeBSD, and some other
725# # BSD variants.
726# #
727# # NOTE: Squid can only determine the MAC/EUI address for IPv4
728# # clients that are on the same subnet. If the client is on a
729# # different subnet, then Squid cannot find out its address.
730# #
731# # NOTE 2: IPv6 protocol does not contain ARP. MAC/EUI is either
732# # encoded directly in the IPv6 address or not available.
733#
734# acl aclname srcdomain .foo.com ...
735# # reverse lookup, from client IP [slow]
736# acl aclname dstdomain [-n] .foo.com ...
737# # Destination server from URL [fast]
738# acl aclname srcdom_regex [-i] \.foo\.com ...
739# # regex matching client name [slow]
740# acl aclname dstdom_regex [-n] [-i] \.foo\.com ...
741# # regex matching server [fast]
742# #
743# # For dstdomain and dstdom_regex a reverse lookup is tried if a IP
744# # based URL is used and no match is found. The name "none" is used
745# # if the reverse lookup fails.
746#
747# acl aclname src_as number ...
748# acl aclname dst_as number ...
749# # [fast]
750# # Except for access control, AS numbers can be used for
751# # routing of requests to specific caches. Here's an
752# # example for routing all requests for AS#1241 and only
753# # those to mycache.mydomain.net:
754# # acl asexample dst_as 1241
755# # cache_peer_access mycache.mydomain.net allow asexample
756# # cache_peer_access mycache_mydomain.net deny all
757#
758# acl aclname peername myPeer ...
759# # [fast]
760# # match against a named cache_peer entry
761# # set unique name= on cache_peer lines for reliable use.
762#
763# acl aclname time [day-abbrevs] [h1:m1-h2:m2]
764# # [fast]
765# # day-abbrevs:
766# # S - Sunday
767# # M - Monday
768# # T - Tuesday
769# # W - Wednesday
770# # H - Thursday
771# # F - Friday
772# # A - Saturday
773# # h1:m1 must be less than h2:m2
774#
775# acl aclname url_regex [-i] ^http:// ...
776# # regex matching on whole URL [fast]
777# acl aclname urllogin [-i] [^a-zA-Z0-9] ...
778# # regex matching on URL login field
779# acl aclname urlpath_regex [-i] \.gif$ ...
780# # regex matching on URL path [fast]
781#
782# acl aclname port 80 70 21 0-1024... # destination TCP port [fast]
783# # ranges are alloed
784# acl aclname localport 3128 ... # TCP port the client connected to [fast]
785# # NP: for interception mode this is usually '80'
786#
787# acl aclname myportname 3128 ... # *_port name [fast]
788#
789# acl aclname proto HTTP FTP ... # request protocol [fast]
790#
791# acl aclname method GET POST ... # HTTP request method [fast]
792#
793# acl aclname http_status 200 301 500- 400-403 ...
794# # status code in reply [fast]
795#
796# acl aclname browser [-i] regexp ...
797# # pattern match on User-Agent header (see also req_header below) [fast]
798#
799# acl aclname referer_regex [-i] regexp ...
800# # pattern match on Referer header [fast]
801# # Referer is highly unreliable, so use with care
802#
803# acl aclname ident username ...
804# acl aclname ident_regex [-i] pattern ...
805# # string match on ident output [slow]
806# # use REQUIRED to accept any non-null ident.
807#
808# acl aclname proxy_auth [-i] username ...
809# acl aclname proxy_auth_regex [-i] pattern ...
810# # perform http authentication challenge to the client and match against
811# # supplied credentials [slow]
812# #
813# # takes a list of allowed usernames.
814# # use REQUIRED to accept any valid username.
815# #
816# # Will use proxy authentication in forward-proxy scenarios, and plain
817# # http authenticaiton in reverse-proxy scenarios
818# #
819# # NOTE: when a Proxy-Authentication header is sent but it is not
820# # needed during ACL checking the username is NOT logged
821# # in access.log.
822# #
823# # NOTE: proxy_auth requires a EXTERNAL authentication program
824# # to check username/password combinations (see
825# # auth_param directive).
826# #
827# # NOTE: proxy_auth can't be used in a transparent/intercepting proxy
828# # as the browser needs to be configured for using a proxy in order
829# # to respond to proxy authentication.
830#
831# acl aclname snmp_community string ...
832# # A community string to limit access to your SNMP Agent [fast]
833# # Example:
834# #
835# # acl snmppublic snmp_community public
836#
837# acl aclname maxconn number
838# # This will be matched when the client's IP address has
839# # more than <number> TCP connections established. [fast]
840# # NOTE: This only measures direct TCP links so X-Forwarded-For
841# # indirect clients are not counted.
842#
843# acl aclname max_user_ip [-s] number
844# # This will be matched when the user attempts to log in from more
845# # than <number> different ip addresses. The authenticate_ip_ttl
846# # parameter controls the timeout on the ip entries. [fast]
847# # If -s is specified the limit is strict, denying browsing
848# # from any further IP addresses until the ttl has expired. Without
849# # -s Squid will just annoy the user by "randomly" denying requests.
850# # (the counter is reset each time the limit is reached and a
851# # request is denied)
852# # NOTE: in acceleration mode or where there is mesh of child proxies,
853# # clients may appear to come from multiple addresses if they are
854# # going through proxy farms, so a limit of 1 may cause user problems.
855#
856# acl aclname random probability
857# # Pseudo-randomly match requests. Based on the probability given.
858# # Probability may be written as a decimal (0.333), fraction (1/3)
859# # or ratio of matches:non-matches (3:5).
860#
861# acl aclname req_mime_type [-i] mime-type ...
862# # regex match against the mime type of the request generated
863# # by the client. Can be used to detect file upload or some
864# # types HTTP tunneling requests [fast]
865# # NOTE: This does NOT match the reply. You cannot use this
866# # to match the returned file type.
867#
868# acl aclname req_header header-name [-i] any\.regex\.here
869# # regex match against any of the known request headers. May be
870# # thought of as a superset of "browser", "referer" and "mime-type"
871# # ACL [fast]
872#
873# acl aclname rep_mime_type [-i] mime-type ...
874# # regex match against the mime type of the reply received by
875# # squid. Can be used to detect file download or some
876# # types HTTP tunneling requests. [fast]
877# # NOTE: This has no effect in http_access rules. It only has
878# # effect in rules that affect the reply data stream such as
879# # http_reply_access.
880#
881# acl aclname rep_header header-name [-i] any\.regex\.here
882# # regex match against any of the known reply headers. May be
883# # thought of as a superset of "browser", "referer" and "mime-type"
884# # ACLs [fast]
885#
886# acl aclname external class_name [arguments...]
887# # external ACL lookup via a helper class defined by the
888# # external_acl_type directive [slow]
889#
890# acl aclname user_cert attribute values...
891# # match against attributes in a user SSL certificate
892# # attribute is one of DN/C/O/CN/L/ST or a numerical OID [fast]
893#
894# acl aclname ca_cert attribute values...
895# # match against attributes a users issuing CA SSL certificate
896# # attribute is one of DN/C/O/CN/L/ST or a numerical OID [fast]
897#
898# acl aclname ext_user username ...
899# acl aclname ext_user_regex [-i] pattern ...
900# # string match on username returned by external acl helper [slow]
901# # use REQUIRED to accept any non-null user name.
902#
903# acl aclname tag tagvalue ...
904# # string match on tag returned by external acl helper [fast]
905# # DEPRECATED. Only the first tag will match with this ACL.
906# # Use the 'note' ACL instead for handling multiple tag values.
907#
908# acl aclname hier_code codename ...
909# # string match against squid hierarchy code(s); [fast]
910# # e.g., DIRECT, PARENT_HIT, NONE, etc.
911# #
912# # NOTE: This has no effect in http_access rules. It only has
913# # effect in rules that affect the reply data stream such as
914# # http_reply_access.
915#
916# acl aclname note name [value ...]
917# # match transaction annotation [fast]
918# # Without values, matches any annotation with a given name.
919# # With value(s), matches any annotation with a given name that
920# # also has one of the given values.
921# # Names and values are compared using a string equality test.
922# # Annotation sources include note and adaptation_meta directives
923# # as well as helper and eCAP responses.
924#
925# acl aclname adaptation_service service ...
926# # Matches the name of any icap_service, ecap_service,
927# # adaptation_service_set, or adaptation_service_chain that Squid
928# # has used (or attempted to use) for the master transaction.
929# # This ACL must be defined after the corresponding adaptation
930# # service is named in squid.conf. This ACL is usable with
931# # adaptation_meta because it starts matching immediately after
932# # the service has been selected for adaptation.
933#
934# acl aclname any-of acl1 acl2 ...
935# # match any one of the acls [fast or slow]
936# # The first matching ACL stops further ACL evaluation.
937# #
938# # ACLs from multiple any-of lines with the same name are ORed.
939# # For example, A = (a1 or a2) or (a3 or a4) can be written as
940# # acl A any-of a1 a2
941# # acl A any-of a3 a4
942# #
943# # This group ACL is fast if all evaluated ACLs in the group are fast
944# # and slow otherwise.
945#
946# acl aclname all-of acl1 acl2 ...
947# # match all of the acls [fast or slow]
948# # The first mismatching ACL stops further ACL evaluation.
949# #
950# # ACLs from multiple all-of lines with the same name are ORed.
951# # For example, B = (b1 and b2) or (b3 and b4) can be written as
952# # acl B all-of b1 b2
953# # acl B all-of b3 b4
954# #
955# # This group ACL is fast if all evaluated ACLs in the group are fast
956# # and slow otherwise.
957#
958# Examples:
959# acl macaddress arp 09:00:2b:23:45:67
960# acl myexample dst_as 1241
961# acl password proxy_auth REQUIRED
962# acl fileupload req_mime_type -i ^multipart/form-data$
963# acl javascript rep_mime_type -i ^application/x-javascript$
964#
965#Default:
966# ACLs all, manager, localhost, and to_localhost are predefined.
967#
968#
969# Recommended minimum configuration:
970#
971
972# Example rule allowing access from your local networks.
973# Adapt to list your (internal) IP networks from where browsing
974# should be allowed
975acl localnet src 10.0.0.0/8 # RFC1918 possible internal network
976acl localnet src 172.16.0.0/12 # RFC1918 possible internal network
977acl localnet src 192.168.0.0/16 # RFC1918 possible internal network
978acl localnet src fc00::/7 # RFC 4193 local private network range
979acl localnet src fe80::/10 # RFC 4291 link-local (directly plugged) machines
980
981acl SSL_ports port 443
982acl Safe_ports port 80 # http
983acl Safe_ports port 21 # ftp
984acl Safe_ports port 443 # https
985acl Safe_ports port 70 # gopher
986acl Safe_ports port 210 # wais
987acl Safe_ports port 1025-65535 # unregistered ports
988acl Safe_ports port 280 # http-mgmt
989acl Safe_ports port 488 # gss-http
990acl Safe_ports port 591 # filemaker
991acl Safe_ports port 777 # multiling http
992acl CONNECT method CONNECT
993
994# TAG: proxy_protocol_access
995# Determine which client proxies can be trusted to provide correct
996# information regarding real client IP address using PROXY protocol.
997#
998# Requests may pass through a chain of several other proxies
999# before reaching us. The original source details may by sent in:
1000# * HTTP message Forwarded header, or
1001# * HTTP message X-Forwarded-For header, or
1002# * PROXY protocol connection header.
1003#
1004# This directive is solely for validating new PROXY protocol
1005# connections received from a port flagged with require-proxy-header.
1006# It is checked only once after TCP connection setup.
1007#
1008# A deny match results in TCP connection closure.
1009#
1010# An allow match is required for Squid to permit the corresponding
1011# TCP connection, before Squid even looks for HTTP request headers.
1012# If there is an allow match, Squid starts using PROXY header information
1013# to determine the source address of the connection for all future ACL
1014# checks, logging, etc.
1015#
1016# SECURITY CONSIDERATIONS:
1017#
1018# Any host from which we accept client IP details can place
1019# incorrect information in the relevant header, and Squid
1020# will use the incorrect information as if it were the
1021# source address of the request. This may enable remote
1022# hosts to bypass any access control restrictions that are
1023# based on the client's source addresses.
1024#
1025# This clause only supports fast acl types.
1026# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1027#Default:
1028# all TCP connections to ports with require-proxy-header will be denied
1029
1030# TAG: follow_x_forwarded_for
1031# Determine which client proxies can be trusted to provide correct
1032# information regarding real client IP address.
1033#
1034# Requests may pass through a chain of several other proxies
1035# before reaching us. The original source details may by sent in:
1036# * HTTP message Forwarded header, or
1037# * HTTP message X-Forwarded-For header, or
1038# * PROXY protocol connection header.
1039#
1040# PROXY protocol connections are controlled by the proxy_protocol_access
1041# directive which is checked before this.
1042#
1043# If a request reaches us from a source that is allowed by this
1044# directive, then we trust the information it provides regarding
1045# the IP of the client it received from (if any).
1046#
1047# For the purpose of ACLs used in this directive the src ACL type always
1048# matches the address we are testing and srcdomain matches its rDNS.
1049#
1050# On each HTTP request Squid checks for X-Forwarded-For header fields.
1051# If found the header values are iterated in reverse order and an allow
1052# match is required for Squid to continue on to the next value.
1053# The verification ends when a value receives a deny match, cannot be
1054# tested, or there are no more values to test.
1055# NOTE: Squid does not yet follow the Forwarded HTTP header.
1056#
1057# The end result of this process is an IP address that we will
1058# refer to as the indirect client address. This address may
1059# be treated as the client address for access control, ICAP, delay
1060# pools and logging, depending on the acl_uses_indirect_client,
1061# icap_uses_indirect_client, delay_pool_uses_indirect_client,
1062# log_uses_indirect_client and tproxy_uses_indirect_client options.
1063#
1064# This clause only supports fast acl types.
1065# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1066#
1067# SECURITY CONSIDERATIONS:
1068#
1069# Any host from which we accept client IP details can place
1070# incorrect information in the relevant header, and Squid
1071# will use the incorrect information as if it were the
1072# source address of the request. This may enable remote
1073# hosts to bypass any access control restrictions that are
1074# based on the client's source addresses.
1075#
1076# For example:
1077#
1078# acl localhost src 127.0.0.1
1079# acl my_other_proxy srcdomain .proxy.example.com
1080# follow_x_forwarded_for allow localhost
1081# follow_x_forwarded_for allow my_other_proxy
1082#Default:
1083# X-Forwarded-For header will be ignored.
1084
1085# TAG: acl_uses_indirect_client on|off
1086# Controls whether the indirect client address
1087# (see follow_x_forwarded_for) is used instead of the
1088# direct client address in acl matching.
1089#
1090# NOTE: maxconn ACL considers direct TCP links and indirect
1091# clients will always have zero. So no match.
1092#Default:
1093# acl_uses_indirect_client on
1094
1095# TAG: delay_pool_uses_indirect_client on|off
1096# Controls whether the indirect client address
1097# (see follow_x_forwarded_for) is used instead of the
1098# direct client address in delay pools.
1099#Default:
1100# delay_pool_uses_indirect_client on
1101
1102# TAG: log_uses_indirect_client on|off
1103# Controls whether the indirect client address
1104# (see follow_x_forwarded_for) is used instead of the
1105# direct client address in the access log.
1106#Default:
1107# log_uses_indirect_client on
1108
1109# TAG: tproxy_uses_indirect_client on|off
1110# Controls whether the indirect client address
1111# (see follow_x_forwarded_for) is used instead of the
1112# direct client address when spoofing the outgoing client.
1113#
1114# This has no effect on requests arriving in non-tproxy
1115# mode ports.
1116#
1117# SECURITY WARNING: Usage of this option is dangerous
1118# and should not be used trivially. Correct configuration
1119# of follow_x_forwarded_for with a limited set of trusted
1120# sources is required to prevent abuse of your proxy.
1121#Default:
1122# tproxy_uses_indirect_client off
1123
1124# TAG: spoof_client_ip
1125# Control client IP address spoofing of TPROXY traffic based on
1126# defined access lists.
1127#
1128# spoof_client_ip allow|deny [!]aclname ...
1129#
1130# If there are no "spoof_client_ip" lines present, the default
1131# is to "allow" spoofing of any suitable request.
1132#
1133# Note that the cache_peer "no-tproxy" option overrides this ACL.
1134#
1135# This clause supports fast acl types.
1136# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1137#Default:
1138# Allow spoofing on all TPROXY traffic.
1139
1140# TAG: http_access
1141# Allowing or Denying access based on defined access lists
1142#
1143# To allow or deny a message received on an HTTP, HTTPS, or FTP port:
1144# http_access allow|deny [!]aclname ...
1145#
1146# NOTE on default values:
1147#
1148# If there are no "access" lines present, the default is to deny
1149# the request.
1150#
1151# If none of the "access" lines cause a match, the default is the
1152# opposite of the last line in the list. If the last line was
1153# deny, the default is allow. Conversely, if the last line
1154# is allow, the default will be deny. For these reasons, it is a
1155# good idea to have an "deny all" entry at the end of your access
1156# lists to avoid potential confusion.
1157#
1158# This clause supports both fast and slow acl types.
1159# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1160#
1161#Default:
1162# Deny, unless rules exist in squid.conf.
1163#
1164
1165#
1166# Recommended minimum Access Permission configuration:
1167#
1168# Deny requests to certain unsafe ports
1169http_access deny !Safe_ports
1170
1171# Deny CONNECT to other than secure SSL ports
1172http_access deny CONNECT !SSL_ports
1173
1174# Only allow cachemgr access from localhost
1175http_access allow localhost manager
1176http_access deny manager
1177
1178# We strongly recommend the following be uncommented to protect innocent
1179# web applications running on the proxy server who think the only
1180# one who can access services on "localhost" is a local user
1181#http_access deny to_localhost
1182
1183#
1184# INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS
1185#
1186
1187# Example rule allowing access from your local networks.
1188# Adapt localnet in the ACL section to list your (internal) IP networks
1189# from where browsing should be allowed
1190http_access allow localnet
1191http_access allow localhost
1192
1193# And finally deny all other access to this proxy
1194http_access deny all
1195
1196# TAG: adapted_http_access
1197# Allowing or Denying access based on defined access lists
1198#
1199# Essentially identical to http_access, but runs after redirectors
1200# and ICAP/eCAP adaptation. Allowing access control based on their
1201# output.
1202#
1203# If not set then only http_access is used.
1204#Default:
1205# Allow, unless rules exist in squid.conf.
1206
1207# TAG: http_reply_access
1208# Allow replies to client requests. This is complementary to http_access.
1209#
1210# http_reply_access allow|deny [!] aclname ...
1211#
1212# NOTE: if there are no access lines present, the default is to allow
1213# all replies.
1214#
1215# If none of the access lines cause a match the opposite of the
1216# last line will apply. Thus it is good practice to end the rules
1217# with an "allow all" or "deny all" entry.
1218#
1219# This clause supports both fast and slow acl types.
1220# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1221#Default:
1222# Allow, unless rules exist in squid.conf.
1223
1224# TAG: icp_access
1225# Allowing or Denying access to the ICP port based on defined
1226# access lists
1227#
1228# icp_access allow|deny [!]aclname ...
1229#
1230# NOTE: The default if no icp_access lines are present is to
1231# deny all traffic. This default may cause problems with peers
1232# using ICP.
1233#
1234# This clause only supports fast acl types.
1235# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1236#
1237## Allow ICP queries from local networks only
1238##icp_access allow localnet
1239##icp_access deny all
1240#Default:
1241# Deny, unless rules exist in squid.conf.
1242
1243# TAG: htcp_access
1244# Allowing or Denying access to the HTCP port based on defined
1245# access lists
1246#
1247# htcp_access allow|deny [!]aclname ...
1248#
1249# See also htcp_clr_access for details on access control for
1250# cache purge (CLR) HTCP messages.
1251#
1252# NOTE: The default if no htcp_access lines are present is to
1253# deny all traffic. This default may cause problems with peers
1254# using the htcp option.
1255#
1256# This clause only supports fast acl types.
1257# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1258#
1259## Allow HTCP queries from local networks only
1260##htcp_access allow localnet
1261##htcp_access deny all
1262#Default:
1263# Deny, unless rules exist in squid.conf.
1264
1265# TAG: htcp_clr_access
1266# Allowing or Denying access to purge content using HTCP based
1267# on defined access lists.
1268# See htcp_access for details on general HTCP access control.
1269#
1270# htcp_clr_access allow|deny [!]aclname ...
1271#
1272# This clause only supports fast acl types.
1273# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1274#
1275## Allow HTCP CLR requests from trusted peers
1276#acl htcp_clr_peer src 192.0.2.2 2001:DB8::2
1277#htcp_clr_access allow htcp_clr_peer
1278#htcp_clr_access deny all
1279#Default:
1280# Deny, unless rules exist in squid.conf.
1281
1282# TAG: miss_access
1283# Determines whether network access is permitted when satisfying a request.
1284#
1285# For example;
1286# to force your neighbors to use you as a sibling instead of
1287# a parent.
1288#
1289# acl localclients src 192.0.2.0/24 2001:DB8::a:0/64
1290# miss_access deny !localclients
1291# miss_access allow all
1292#
1293# This means only your local clients are allowed to fetch relayed/MISS
1294# replies from the network and all other clients can only fetch cached
1295# objects (HITs).
1296#
1297# The default for this setting allows all clients who passed the
1298# http_access rules to relay via this proxy.
1299#
1300# This clause only supports fast acl types.
1301# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1302#Default:
1303# Allow, unless rules exist in squid.conf.
1304
1305# TAG: ident_lookup_access
1306# A list of ACL elements which, if matched, cause an ident
1307# (RFC 931) lookup to be performed for this request. For
1308# example, you might choose to always perform ident lookups
1309# for your main multi-user Unix boxes, but not for your Macs
1310# and PCs. By default, ident lookups are not performed for
1311# any requests.
1312#
1313# To enable ident lookups for specific client addresses, you
1314# can follow this example:
1315#
1316# acl ident_aware_hosts src 198.168.1.0/24
1317# ident_lookup_access allow ident_aware_hosts
1318# ident_lookup_access deny all
1319#
1320# Only src type ACL checks are fully supported. A srcdomain
1321# ACL might work at times, but it will not always provide
1322# the correct result.
1323#
1324# This clause only supports fast acl types.
1325# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1326#Default:
1327# Unless rules exist in squid.conf, IDENT is not fetched.
1328
1329# TAG: reply_body_max_size size [acl acl...]
1330# This option specifies the maximum size of a reply body. It can be
1331# used to prevent users from downloading very large files, such as
1332# MP3's and movies. When the reply headers are received, the
1333# reply_body_max_size lines are processed, and the first line where
1334# all (if any) listed ACLs are true is used as the maximum body size
1335# for this reply.
1336#
1337# This size is checked twice. First when we get the reply headers,
1338# we check the content-length value. If the content length value exists
1339# and is larger than the allowed size, the request is denied and the
1340# user receives an error message that says "the request or reply
1341# is too large." If there is no content-length, and the reply
1342# size exceeds this limit, the client's connection is just closed
1343# and they will receive a partial reply.
1344#
1345# WARNING: downstream caches probably can not detect a partial reply
1346# if there is no content-length header, so they will cache
1347# partial responses and give them out as hits. You should NOT
1348# use this option if you have downstream caches.
1349#
1350# WARNING: A maximum size smaller than the size of squid's error messages
1351# will cause an infinite loop and crash squid. Ensure that the smallest
1352# non-zero value you use is greater that the maximum header size plus
1353# the size of your largest error page.
1354#
1355# If you set this parameter none (the default), there will be
1356# no limit imposed.
1357#
1358# Configuration Format is:
1359# reply_body_max_size SIZE UNITS [acl ...]
1360# ie.
1361# reply_body_max_size 10 MB
1362#
1363#Default:
1364# No limit is applied.
1365
1366# NETWORK OPTIONS
1367# -----------------------------------------------------------------------------
1368
1369# TAG: http_port
1370# Usage: port [mode] [options]
1371# hostname:port [mode] [options]
1372# 1.2.3.4:port [mode] [options]
1373#
1374# The socket addresses where Squid will listen for HTTP client
1375# requests. You may specify multiple socket addresses.
1376# There are three forms: port alone, hostname with port, and
1377# IP address with port. If you specify a hostname or IP
1378# address, Squid binds the socket to that specific
1379# address. Most likely, you do not need to bind to a specific
1380# address, so you can use the port number alone.
1381#
1382# If you are running Squid in accelerator mode, you
1383# probably want to listen on port 80 also, or instead.
1384#
1385# The -a command line option may be used to specify additional
1386# port(s) where Squid listens for proxy request. Such ports will
1387# be plain proxy ports with no options.
1388#
1389# You may specify multiple socket addresses on multiple lines.
1390#
1391# Modes:
1392#
1393# intercept Support for IP-Layer NAT interception delivering
1394# traffic to this Squid port.
1395# NP: disables authentication on the port.
1396#
1397# tproxy Support Linux TPROXY (or BSD divert-to) with spoofing
1398# of outgoing connections using the client IP address.
1399# NP: disables authentication on the port.
1400#
1401# accel Accelerator / reverse proxy mode
1402#
1403# ssl-bump For each CONNECT request allowed by ssl_bump ACLs,
1404# establish secure connection with the client and with
1405# the server, decrypt HTTPS messages as they pass through
1406# Squid, and treat them as unencrypted HTTP messages,
1407# becoming the man-in-the-middle.
1408#
1409# The ssl_bump option is required to fully enable
1410# bumping of CONNECT requests.
1411#
1412# Omitting the mode flag causes default forward proxy mode to be used.
1413#
1414#
1415# Accelerator Mode Options:
1416#
1417# defaultsite=domainname
1418# What to use for the Host: header if it is not present
1419# in a request. Determines what site (not origin server)
1420# accelerators should consider the default.
1421#
1422# no-vhost Disable using HTTP/1.1 Host header for virtual domain support.
1423#
1424# protocol= Protocol to reconstruct accelerated and intercepted
1425# requests with. Defaults to HTTP/1.1 for http_port and
1426# HTTPS/1.1 for https_port.
1427# When an unsupported value is configured Squid will
1428# produce a FATAL error.
1429# Values: HTTP or HTTP/1.1, HTTPS or HTTPS/1.1
1430#
1431# vport Virtual host port support. Using the http_port number
1432# instead of the port passed on Host: headers.
1433#
1434# vport=NN Virtual host port support. Using the specified port
1435# number instead of the port passed on Host: headers.
1436#
1437# act-as-origin
1438# Act as if this Squid is the origin server.
1439# This currently means generate new Date: and Expires:
1440# headers on HIT instead of adding Age:.
1441#
1442# ignore-cc Ignore request Cache-Control headers.
1443#
1444# WARNING: This option violates HTTP specifications if
1445# used in non-accelerator setups.
1446#
1447# allow-direct Allow direct forwarding in accelerator mode. Normally
1448# accelerated requests are denied direct forwarding as if
1449# never_direct was used.
1450#
1451# WARNING: this option opens accelerator mode to security
1452# vulnerabilities usually only affecting in interception
1453# mode. Make sure to protect forwarding with suitable
1454# http_access rules when using this.
1455#
1456#
1457# SSL Bump Mode Options:
1458# In addition to these options ssl-bump requires TLS/SSL options.
1459#
1460# generate-host-certificates[=<on|off>]
1461# Dynamically create SSL server certificates for the
1462# destination hosts of bumped CONNECT requests.When
1463# enabled, the cert and key options are used to sign
1464# generated certificates. Otherwise generated
1465# certificate will be selfsigned.
1466# If there is a CA certificate lifetime of the generated
1467# certificate equals lifetime of the CA certificate. If
1468# generated certificate is selfsigned lifetime is three
1469# years.
1470# This option is disabled by default. See the ssl-bump
1471# option above for more information.
1472#
1473# dynamic_cert_mem_cache_size=SIZE
1474# Approximate total RAM size spent on cached generated
1475# certificates. If set to zero, caching is disabled.
1476#
1477# TLS / SSL Options:
1478#
1479# cert= Path to SSL certificate (PEM format).
1480#
1481# key= Path to SSL private key file (PEM format)
1482# if not specified, the certificate file is
1483# assumed to be a combined certificate and
1484# key file.
1485#
1486# version= The version of SSL/TLS supported
1487# 1 automatic (default)
1488# 2 SSLv2 only
1489# 3 SSLv3 only
1490# 4 TLSv1.0 only
1491# 5 TLSv1.1 only
1492# 6 TLSv1.2 only
1493#
1494# cipher= Colon separated list of supported ciphers.
1495# NOTE: some ciphers such as EDH ciphers depend on
1496# additional settings. If those settings are
1497# omitted the ciphers may be silently ignored
1498# by the OpenSSL library.
1499#
1500# options= Various SSL implementation options. The most important
1501# being:
1502# NO_SSLv2 Disallow the use of SSLv2
1503# NO_SSLv3 Disallow the use of SSLv3
1504# NO_TLSv1 Disallow the use of TLSv1.0
1505# NO_TLSv1_1 Disallow the use of TLSv1.1
1506# NO_TLSv1_2 Disallow the use of TLSv1.2
1507# SINGLE_DH_USE Always create a new key when using
1508# temporary/ephemeral DH key exchanges
1509# NO_TICKET Disables TLS tickets extension
1510#
1511# SINGLE_ECDH_USE
1512# Enable ephemeral ECDH key exchange.
1513# The adopted curve should be specified
1514# using the tls-dh option.
1515#
1516# ALL Enable various bug workarounds
1517# suggested as "harmless" by OpenSSL
1518# Be warned that this reduces SSL/TLS
1519# strength to some attacks.
1520# See OpenSSL SSL_CTX_set_options documentation for a
1521# complete list of options.
1522#
1523# clientca= File containing the list of CAs to use when
1524# requesting a client certificate.
1525#
1526# cafile= File containing additional CA certificates to
1527# use when verifying client certificates. If unset
1528# clientca will be used.
1529#
1530# capath= Directory containing additional CA certificates
1531# and CRL lists to use when verifying client certificates.
1532#
1533# crlfile= File of additional CRL lists to use when verifying
1534# the client certificate, in addition to CRLs stored in
1535# the capath. Implies VERIFY_CRL flag below.
1536#
1537# tls-dh=[curve:]file
1538# File containing DH parameters for temporary/ephemeral DH key
1539# exchanges, optionally prefixed by a curve for ephemeral ECDH
1540# key exchanges.
1541# See OpenSSL documentation for details on how to create the
1542# DH parameter file. Supported curves for ECDH can be listed
1543# using the "openssl ecparam -list_curves" command.
1544# WARNING: EDH and EECDH ciphers will be silently disabled if
1545# this option is not set.
1546#
1547# sslflags= Various flags modifying the use of SSL:
1548# DELAYED_AUTH
1549# Don't request client certificates
1550# immediately, but wait until acl processing
1551# requires a certificate (not yet implemented).
1552# NO_DEFAULT_CA
1553# Don't use the default CA lists built in
1554# to OpenSSL.
1555# NO_SESSION_REUSE
1556# Don't allow for session reuse. Each connection
1557# will result in a new SSL session.
1558# VERIFY_CRL
1559# Verify CRL lists when accepting client
1560# certificates.
1561# VERIFY_CRL_ALL
1562# Verify CRL lists for all certificates in the
1563# client certificate chain.
1564#
1565# sslcontext= SSL session ID context identifier.
1566#
1567# Other Options:
1568#
1569# connection-auth[=on|off]
1570# use connection-auth=off to tell Squid to prevent
1571# forwarding Microsoft connection oriented authentication
1572# (NTLM, Negotiate and Kerberos)
1573#
1574# disable-pmtu-discovery=
1575# Control Path-MTU discovery usage:
1576# off lets OS decide on what to do (default).
1577# transparent disable PMTU discovery when transparent
1578# support is enabled.
1579# always disable always PMTU discovery.
1580#
1581# In many setups of transparently intercepting proxies
1582# Path-MTU discovery can not work on traffic towards the
1583# clients. This is the case when the intercepting device
1584# does not fully track connections and fails to forward
1585# ICMP must fragment messages to the cache server. If you
1586# have such setup and experience that certain clients
1587# sporadically hang or never complete requests set
1588# disable-pmtu-discovery option to 'transparent'.
1589#
1590# name= Specifies a internal name for the port. Defaults to
1591# the port specification (port or addr:port)
1592#
1593# tcpkeepalive[=idle,interval,timeout]
1594# Enable TCP keepalive probes of idle connections.
1595# In seconds; idle is the initial time before TCP starts
1596# probing the connection, interval how often to probe, and
1597# timeout the time before giving up.
1598#
1599# require-proxy-header
1600# Require PROXY protocol version 1 or 2 connections.
1601# The proxy_protocol_access is required to whitelist
1602# downstream proxies which can be trusted.
1603#
1604# If you run Squid on a dual-homed machine with an internal
1605# and an external interface we recommend you to specify the
1606# internal address:port in http_port. This way Squid will only be
1607# visible on the internal address.
1608#
1609#
1610
1611# Squid normally listens to port 3128
1612http_port 3128
1613
1614# TAG: https_port
1615# Note: This option is only available if Squid is rebuilt with the
1616# --with-openssl
1617#
1618# Usage: [ip:]port cert=certificate.pem [key=key.pem] [mode] [options...]
1619#
1620# The socket address where Squid will listen for client requests made
1621# over TLS or SSL connections. Commonly referred to as HTTPS.
1622#
1623# This is most useful for situations where you are running squid in
1624# accelerator mode and you want to do the SSL work at the accelerator level.
1625#
1626# You may specify multiple socket addresses on multiple lines,
1627# each with their own SSL certificate and/or options.
1628#
1629# Modes:
1630#
1631# accel Accelerator / reverse proxy mode
1632#
1633# intercept Support for IP-Layer interception of
1634# outgoing requests without browser settings.
1635# NP: disables authentication and IPv6 on the port.
1636#
1637# tproxy Support Linux TPROXY for spoofing outgoing
1638# connections using the client IP address.
1639# NP: disables authentication and maybe IPv6 on the port.
1640#
1641# ssl-bump For each intercepted connection allowed by ssl_bump
1642# ACLs, establish a secure connection with the client and with
1643# the server, decrypt HTTPS messages as they pass through
1644# Squid, and treat them as unencrypted HTTP messages,
1645# becoming the man-in-the-middle.
1646#
1647# An "ssl_bump server-first" match is required to
1648# fully enable bumping of intercepted SSL connections.
1649#
1650# Requires tproxy or intercept.
1651#
1652# Omitting the mode flag causes default forward proxy mode to be used.
1653#
1654#
1655# See http_port for a list of generic options
1656#
1657#
1658# SSL Options:
1659#
1660# cert= Path to SSL certificate (PEM format).
1661#
1662# key= Path to SSL private key file (PEM format)
1663# if not specified, the certificate file is
1664# assumed to be a combined certificate and
1665# key file.
1666#
1667# version= The version of SSL/TLS supported
1668# 1 automatic (default)
1669# 2 SSLv2 only
1670# 3 SSLv3 only
1671# 4 TLSv1 only
1672#
1673# cipher= Colon separated list of supported ciphers.
1674#
1675# options= Various SSL engine options. The most important
1676# being:
1677# NO_SSLv2 Disallow the use of SSLv2
1678# NO_SSLv3 Disallow the use of SSLv3
1679# NO_TLSv1 Disallow the use of TLSv1
1680#
1681# SINGLE_DH_USE Always create a new key when using
1682# temporary/ephemeral DH key exchanges
1683#
1684# SINGLE_ECDH_USE
1685# Enable ephemeral ECDH key exchange.
1686# The adopted curve should be specified
1687# using the tls-dh option.
1688#
1689# See src/ssl_support.c or OpenSSL SSL_CTX_set_options
1690# documentation for a complete list of options.
1691#
1692# clientca= File containing the list of CAs to use when
1693# requesting a client certificate.
1694#
1695# cafile= File containing additional CA certificates to
1696# use when verifying client certificates. If unset
1697# clientca will be used.
1698#
1699# capath= Directory containing additional CA certificates
1700# and CRL lists to use when verifying client certificates.
1701#
1702# crlfile= File of additional CRL lists to use when verifying
1703# the client certificate, in addition to CRLs stored in
1704# the capath. Implies VERIFY_CRL flag below.
1705#
1706# tls-dh=[curve:]file
1707# File containing DH parameters for temporary/ephemeral DH key
1708# exchanges, optionally prefixed by a curve for ephemeral ECDH
1709# key exchanges.
1710#
1711# sslflags= Various flags modifying the use of SSL:
1712# DELAYED_AUTH
1713# Don't request client certificates
1714# immediately, but wait until acl processing
1715# requires a certificate (not yet implemented).
1716# NO_DEFAULT_CA
1717# Don't use the default CA lists built in
1718# to OpenSSL.
1719# NO_SESSION_REUSE
1720# Don't allow for session reuse. Each connection
1721# will result in a new SSL session.
1722# VERIFY_CRL
1723# Verify CRL lists when accepting client
1724# certificates.
1725# VERIFY_CRL_ALL
1726# Verify CRL lists for all certificates in the
1727# client certificate chain.
1728#
1729# sslcontext= SSL session ID context identifier.
1730#
1731# generate-host-certificates[=<on|off>]
1732# Dynamically create SSL server certificates for the
1733# destination hosts of bumped SSL requests.When
1734# enabled, the cert and key options are used to sign
1735# generated certificates. Otherwise generated
1736# certificate will be selfsigned.
1737# If there is CA certificate life time of generated
1738# certificate equals lifetime of CA certificate. If
1739# generated certificate is selfsigned lifetime is three
1740# years.
1741# This option is disabled by default. See the ssl-bump
1742# option above for more information.
1743#
1744# dynamic_cert_mem_cache_size=SIZE
1745# Approximate total RAM size spent on cached generated
1746# certificates. If set to zero, caching is disabled.
1747#
1748# See http_port for a list of available options.
1749#Default:
1750# none
1751
1752# TAG: ftp_port
1753# Enables Native FTP proxy by specifying the socket address where Squid
1754# listens for FTP client requests. See http_port directive for various
1755# ways to specify the listening address and mode.
1756#
1757# Usage: ftp_port address [mode] [options]
1758#
1759# WARNING: This is a new, experimental, complex feature that has seen
1760# limited production exposure. Some Squid modules (e.g., caching) do not
1761# currently work with native FTP proxying, and many features have not
1762# even been tested for compatibility. Test well before deploying!
1763#
1764# Native FTP proxying differs substantially from proxying HTTP requests
1765# with ftp:// URIs because Squid works as an FTP server and receives
1766# actual FTP commands (rather than HTTP requests with FTP URLs).
1767#
1768# Native FTP commands accepted at ftp_port are internally converted or
1769# wrapped into HTTP-like messages. The same happens to Native FTP
1770# responses received from FTP origin servers. Those HTTP-like messages
1771# are shoveled through regular access control and adaptation layers
1772# between the FTP client and the FTP origin server. This allows Squid to
1773# examine, adapt, block, and log FTP exchanges. Squid reuses most HTTP
1774# mechanisms when shoveling wrapped FTP messages. For example,
1775# http_access and adaptation_access directives are used.
1776#
1777# Modes:
1778#
1779# intercept Same as http_port intercept. The FTP origin address is
1780# determined based on the intended destination of the
1781# intercepted connection.
1782#
1783# tproxy Support Linux TPROXY for spoofing outgoing
1784# connections using the client IP address.
1785# NP: disables authentication and maybe IPv6 on the port.
1786#
1787# By default (i.e., without an explicit mode option), Squid extracts the
1788# FTP origin address from the login@origin parameter of the FTP USER
1789# command. Many popular FTP clients support such native FTP proxying.
1790#
1791# Options:
1792#
1793# name=token Specifies an internal name for the port. Defaults to
1794# the port address. Usable with myportname ACL.
1795#
1796# ftp-track-dirs
1797# Enables tracking of FTP directories by injecting extra
1798# PWD commands and adjusting Request-URI (in wrapping
1799# HTTP requests) to reflect the current FTP server
1800# directory. Tracking is disabled by default.
1801#
1802# protocol=FTP Protocol to reconstruct accelerated and intercepted
1803# requests with. Defaults to FTP. No other accepted
1804# values have been tested with. An unsupported value
1805# results in a FATAL error. Accepted values are FTP,
1806# HTTP (or HTTP/1.1), and HTTPS (or HTTPS/1.1).
1807#
1808# Other http_port modes and options that are not specific to HTTP and
1809# HTTPS may also work.
1810#Default:
1811# none
1812
1813# TAG: tcp_outgoing_tos
1814# Allows you to select a TOS/Diffserv value for packets outgoing
1815# on the server side, based on an ACL.
1816#
1817# tcp_outgoing_tos ds-field [!]aclname ...
1818#
1819# Example where normal_service_net uses the TOS value 0x00
1820# and good_service_net uses 0x20
1821#
1822# acl normal_service_net src 10.0.0.0/24
1823# acl good_service_net src 10.0.1.0/24
1824# tcp_outgoing_tos 0x00 normal_service_net
1825# tcp_outgoing_tos 0x20 good_service_net
1826#
1827# TOS/DSCP values really only have local significance - so you should
1828# know what you're specifying. For more information, see RFC2474,
1829# RFC2475, and RFC3260.
1830#
1831# The TOS/DSCP byte must be exactly that - a octet value 0 - 255, or
1832# "default" to use whatever default your host has.
1833# Note that only multiples of 4 are usable as the two rightmost bits have
1834# been redefined for use by ECN (RFC 3168 section 23.1).
1835# The squid parser will enforce this by masking away the ECN bits.
1836#
1837# Processing proceeds in the order specified, and stops at first fully
1838# matching line.
1839#
1840# Only fast ACLs are supported.
1841#Default:
1842# none
1843
1844# TAG: clientside_tos
1845# Allows you to select a TOS/DSCP value for packets being transmitted
1846# on the client-side, based on an ACL.
1847#
1848# clientside_tos ds-field [!]aclname ...
1849#
1850# Example where normal_service_net uses the TOS value 0x00
1851# and good_service_net uses 0x20
1852#
1853# acl normal_service_net src 10.0.0.0/24
1854# acl good_service_net src 10.0.1.0/24
1855# clientside_tos 0x00 normal_service_net
1856# clientside_tos 0x20 good_service_net
1857#
1858# Note: This feature is incompatible with qos_flows. Any TOS values set here
1859# will be overwritten by TOS values in qos_flows.
1860#
1861# The TOS/DSCP byte must be exactly that - a octet value 0 - 255, or
1862# "default" to use whatever default your host has.
1863# Note that only multiples of 4 are usable as the two rightmost bits have
1864# been redefined for use by ECN (RFC 3168 section 23.1).
1865# The squid parser will enforce this by masking away the ECN bits.
1866#
1867#Default:
1868# none
1869
1870# TAG: tcp_outgoing_mark
1871# Note: This option is only available if Squid is rebuilt with the
1872# Packet MARK (Linux)
1873#
1874# Allows you to apply a Netfilter mark value to outgoing packets
1875# on the server side, based on an ACL.
1876#
1877# tcp_outgoing_mark mark-value [!]aclname ...
1878#
1879# Example where normal_service_net uses the mark value 0x00
1880# and good_service_net uses 0x20
1881#
1882# acl normal_service_net src 10.0.0.0/24
1883# acl good_service_net src 10.0.1.0/24
1884# tcp_outgoing_mark 0x00 normal_service_net
1885# tcp_outgoing_mark 0x20 good_service_net
1886#
1887# Only fast ACLs are supported.
1888#Default:
1889# none
1890
1891# TAG: clientside_mark
1892# Note: This option is only available if Squid is rebuilt with the
1893# Packet MARK (Linux)
1894#
1895# Allows you to apply a Netfilter mark value to packets being transmitted
1896# on the client-side, based on an ACL.
1897#
1898# clientside_mark mark-value [!]aclname ...
1899#
1900# Example where normal_service_net uses the mark value 0x00
1901# and good_service_net uses 0x20
1902#
1903# acl normal_service_net src 10.0.0.0/24
1904# acl good_service_net src 10.0.1.0/24
1905# clientside_mark 0x00 normal_service_net
1906# clientside_mark 0x20 good_service_net
1907#
1908# Note: This feature is incompatible with qos_flows. Any mark values set here
1909# will be overwritten by mark values in qos_flows.
1910#Default:
1911# none
1912
1913# TAG: qos_flows
1914# Allows you to select a TOS/DSCP value to mark outgoing
1915# connections to the client, based on where the reply was sourced.
1916# For platforms using netfilter, allows you to set a netfilter mark
1917# value instead of, or in addition to, a TOS value.
1918#
1919# By default this functionality is disabled. To enable it with the default
1920# settings simply use "qos_flows mark" or "qos_flows tos". Default
1921# settings will result in the netfilter mark or TOS value being copied
1922# from the upstream connection to the client. Note that it is the connection
1923# CONNMARK value not the packet MARK value that is copied.
1924#
1925# It is not currently possible to copy the mark or TOS value from the
1926# client to the upstream connection request.
1927#
1928# TOS values really only have local significance - so you should
1929# know what you're specifying. For more information, see RFC2474,
1930# RFC2475, and RFC3260.
1931#
1932# The TOS/DSCP byte must be exactly that - a octet value 0 - 255.
1933# Note that only multiples of 4 are usable as the two rightmost bits have
1934# been redefined for use by ECN (RFC 3168 section 23.1).
1935# The squid parser will enforce this by masking away the ECN bits.
1936#
1937# Mark values can be any unsigned 32-bit integer value.
1938#
1939# This setting is configured by setting the following values:
1940#
1941# tos|mark Whether to set TOS or netfilter mark values
1942#
1943# local-hit=0xFF Value to mark local cache hits.
1944#
1945# sibling-hit=0xFF Value to mark hits from sibling peers.
1946#
1947# parent-hit=0xFF Value to mark hits from parent peers.
1948#
1949# miss=0xFF[/mask] Value to mark cache misses. Takes precedence
1950# over the preserve-miss feature (see below), unless
1951# mask is specified, in which case only the bits
1952# specified in the mask are written.
1953#
1954# The TOS variant of the following features are only possible on Linux
1955# and require your kernel to be patched with the TOS preserving ZPH
1956# patch, available from http://zph.bratcheda.org
1957# No patch is needed to preserve the netfilter mark, which will work
1958# with all variants of netfilter.
1959#
1960# disable-preserve-miss
1961# This option disables the preservation of the TOS or netfilter
1962# mark. By default, the existing TOS or netfilter mark value of
1963# the response coming from the remote server will be retained
1964# and masked with miss-mark.
1965# NOTE: in the case of a netfilter mark, the mark must be set on
1966# the connection (using the CONNMARK target) not on the packet
1967# (MARK target).
1968#
1969# miss-mask=0xFF
1970# Allows you to mask certain bits in the TOS or mark value
1971# received from the remote server, before copying the value to
1972# the TOS sent towards clients.
1973# Default for tos: 0xFF (TOS from server is not changed).
1974# Default for mark: 0xFFFFFFFF (mark from server is not changed).
1975#
1976# All of these features require the --enable-zph-qos compilation flag
1977# (enabled by default). Netfilter marking also requires the
1978# libnetfilter_conntrack libraries (--with-netfilter-conntrack) and
1979# libcap 2.09+ (--with-libcap).
1980#
1981#Default:
1982# none
1983
1984# TAG: tcp_outgoing_address
1985# Allows you to map requests to different outgoing IP addresses
1986# based on the username or source address of the user making
1987# the request.
1988#
1989# tcp_outgoing_address ipaddr [[!]aclname] ...
1990#
1991# For example;
1992# Forwarding clients with dedicated IPs for certain subnets.
1993#
1994# acl normal_service_net src 10.0.0.0/24
1995# acl good_service_net src 10.0.2.0/24
1996#
1997# tcp_outgoing_address 2001:db8::c001 good_service_net
1998# tcp_outgoing_address 10.1.0.2 good_service_net
1999#
2000# tcp_outgoing_address 2001:db8::beef normal_service_net
2001# tcp_outgoing_address 10.1.0.1 normal_service_net
2002#
2003# tcp_outgoing_address 2001:db8::1
2004# tcp_outgoing_address 10.1.0.3
2005#
2006# Processing proceeds in the order specified, and stops at first fully
2007# matching line.
2008#
2009# Squid will add an implicit IP version test to each line.
2010# Requests going to IPv4 websites will use the outgoing 10.1.0.* addresses.
2011# Requests going to IPv6 websites will use the outgoing 2001:db8:* addresses.
2012#
2013#
2014# NOTE: The use of this directive using client dependent ACLs is
2015# incompatible with the use of server side persistent connections. To
2016# ensure correct results it is best to set server_persistent_connections
2017# to off when using this directive in such configurations.
2018#
2019# NOTE: The use of this directive to set a local IP on outgoing TCP links
2020# is incompatible with using TPROXY to set client IP out outbound TCP links.
2021# When needing to contact peers use the no-tproxy cache_peer option and the
2022# client_dst_passthru directive re-enable normal forwarding such as this.
2023#
2024#Default:
2025# Address selection is performed by the operating system.
2026
2027# TAG: host_verify_strict
2028# Regardless of this option setting, when dealing with intercepted
2029# traffic, Squid always verifies that the destination IP address matches
2030# the Host header domain or IP (called 'authority form URL').
2031#
2032# This enforcement is performed to satisfy a MUST-level requirement in
2033# RFC 2616 section 14.23: "The Host field value MUST represent the naming
2034# authority of the origin server or gateway given by the original URL".
2035#
2036# When set to ON:
2037# Squid always responds with an HTTP 409 (Conflict) error
2038# page and logs a security warning if there is no match.
2039#
2040# Squid verifies that the destination IP address matches
2041# the Host header for forward-proxy and reverse-proxy traffic
2042# as well. For those traffic types, Squid also enables the
2043# following checks, comparing the corresponding Host header
2044# and Request-URI components:
2045#
2046# * The host names (domain or IP) must be identical,
2047# but valueless or missing Host header disables all checks.
2048# For the two host names to match, both must be either IP
2049# or FQDN.
2050#
2051# * Port numbers must be identical, but if a port is missing
2052# the scheme-default port is assumed.
2053#
2054#
2055# When set to OFF (the default):
2056# Squid allows suspicious requests to continue but logs a
2057# security warning and blocks caching of the response.
2058#
2059# * Forward-proxy traffic is not checked at all.
2060#
2061# * Reverse-proxy traffic is not checked at all.
2062#
2063# * Intercepted traffic which passes verification is handled
2064# according to client_dst_passthru.
2065#
2066# * Intercepted requests which fail verification are sent
2067# to the client original destination instead of DIRECT.
2068# This overrides 'client_dst_passthru off'.
2069#
2070# For now suspicious intercepted CONNECT requests are always
2071# responded to with an HTTP 409 (Conflict) error page.
2072#
2073#
2074# SECURITY NOTE:
2075#
2076# As described in CVE-2009-0801 when the Host: header alone is used
2077# to determine the destination of a request it becomes trivial for
2078# malicious scripts on remote websites to bypass browser same-origin
2079# security policy and sandboxing protections.
2080#
2081# The cause of this is that such applets are allowed to perform their
2082# own HTTP stack, in which case the same-origin policy of the browser
2083# sandbox only verifies that the applet tries to contact the same IP
2084# as from where it was loaded at the IP level. The Host: header may
2085# be different from the connected IP and approved origin.
2086#
2087#Default:
2088# host_verify_strict off
2089
2090# TAG: client_dst_passthru
2091# With NAT or TPROXY intercepted traffic Squid may pass the request
2092# directly to the original client destination IP or seek a faster
2093# source using the HTTP Host header.
2094#
2095# Using Host to locate alternative servers can provide faster
2096# connectivity with a range of failure recovery options.
2097# But can also lead to connectivity trouble when the client and
2098# server are attempting stateful interactions unaware of the proxy.
2099#
2100# This option (on by default) prevents alternative DNS entries being
2101# located to send intercepted traffic DIRECT to an origin server.
2102# The clients original destination IP and port will be used instead.
2103#
2104# Regardless of this option setting, when dealing with intercepted
2105# traffic Squid will verify the Host: header and any traffic which
2106# fails Host verification will be treated as if this option were ON.
2107#
2108# see host_verify_strict for details on the verification process.
2109#Default:
2110# client_dst_passthru on
2111
2112# SSL OPTIONS
2113# -----------------------------------------------------------------------------
2114
2115# TAG: ssl_unclean_shutdown
2116# Note: This option is only available if Squid is rebuilt with the
2117# --with-openssl
2118#
2119# Some browsers (especially MSIE) bugs out on SSL shutdown
2120# messages.
2121#Default:
2122# ssl_unclean_shutdown off
2123
2124# TAG: ssl_engine
2125# Note: This option is only available if Squid is rebuilt with the
2126# --with-openssl
2127#
2128# The OpenSSL engine to use. You will need to set this if you
2129# would like to use hardware SSL acceleration for example.
2130#Default:
2131# none
2132
2133# TAG: sslproxy_client_certificate
2134# Note: This option is only available if Squid is rebuilt with the
2135# --with-openssl
2136#
2137# Client SSL Certificate to use when proxying https:// URLs
2138#Default:
2139# none
2140
2141# TAG: sslproxy_client_key
2142# Note: This option is only available if Squid is rebuilt with the
2143# --with-openssl
2144#
2145# Client SSL Key to use when proxying https:// URLs
2146#Default:
2147# none
2148
2149# TAG: sslproxy_version
2150# Note: This option is only available if Squid is rebuilt with the
2151# --with-openssl
2152#
2153# SSL version level to use when proxying https:// URLs
2154#
2155# The versions of SSL/TLS supported:
2156#
2157# 1 automatic (default)
2158# 2 SSLv2 only
2159# 3 SSLv3 only
2160# 4 TLSv1.0 only
2161# 5 TLSv1.1 only
2162# 6 TLSv1.2 only
2163#Default:
2164# automatic SSL/TLS version negotiation
2165
2166# TAG: sslproxy_options
2167# Note: This option is only available if Squid is rebuilt with the
2168# --with-openssl
2169#
2170# Colon (:) or comma (,) separated list of SSL implementation options
2171# to use when proxying https:// URLs
2172#
2173# The most important being:
2174#
2175# NO_SSLv2 Disallow the use of SSLv2
2176# NO_SSLv3 Disallow the use of SSLv3
2177# NO_TLSv1 Disallow the use of TLSv1.0
2178# NO_TLSv1_1 Disallow the use of TLSv1.1
2179# NO_TLSv1_2 Disallow the use of TLSv1.2
2180#
2181# SINGLE_DH_USE
2182# Always create a new key when using temporary/ephemeral
2183# DH key exchanges
2184#
2185# NO_TICKET
2186# Disable use of RFC5077 session tickets. Some servers
2187# may have problems understanding the TLS extension due
2188# to ambiguous specification in RFC4507.
2189#
2190# ALL Enable various bug workarounds suggested as "harmless"
2191# by OpenSSL. Be warned that this may reduce SSL/TLS
2192# strength to some attacks.
2193#
2194# See the OpenSSL SSL_CTX_set_options documentation for a
2195# complete list of possible options.
2196#
2197# WARNING: This directive takes a single token. If a space is used
2198# the value(s) after that space are SILENTLY IGNORED.
2199#Default:
2200# none
2201
2202# TAG: sslproxy_cipher
2203# Note: This option is only available if Squid is rebuilt with the
2204# --with-openssl
2205#
2206# SSL cipher list to use when proxying https:// URLs
2207#
2208# Colon separated list of supported ciphers.
2209#Default:
2210# none
2211
2212# TAG: sslproxy_cafile
2213# Note: This option is only available if Squid is rebuilt with the
2214# --with-openssl
2215#
2216# file containing CA certificates to use when verifying server
2217# certificates while proxying https:// URLs
2218#Default:
2219# none
2220
2221# TAG: sslproxy_capath
2222# Note: This option is only available if Squid is rebuilt with the
2223# --with-openssl
2224#
2225# directory containing CA certificates to use when verifying
2226# server certificates while proxying https:// URLs
2227#Default:
2228# none
2229
2230# TAG: sslproxy_session_ttl
2231# Note: This option is only available if Squid is rebuilt with the
2232# --with-openssl
2233#
2234# Sets the timeout value for SSL sessions
2235#Default:
2236# sslproxy_session_ttl 300
2237
2238# TAG: sslproxy_session_cache_size
2239# Note: This option is only available if Squid is rebuilt with the
2240# --with-openssl
2241#
2242# Sets the cache size to use for ssl session
2243#Default:
2244# sslproxy_session_cache_size 2 MB
2245
2246# TAG: sslproxy_foreign_intermediate_certs
2247# Note: This option is only available if Squid is rebuilt with the
2248# --with-openssl
2249#
2250# Many origin servers fail to send their full server certificate
2251# chain for verification, assuming the client already has or can
2252# easily locate any missing intermediate certificates.
2253#
2254# Squid uses the certificates from the specified file to fill in
2255# these missing chains when trying to validate origin server
2256# certificate chains.
2257#
2258# The file is expected to contain zero or more PEM-encoded
2259# intermediate certificates. These certificates are not treated
2260# as trusted root certificates, and any self-signed certificate in
2261# this file will be ignored.
2262#Default:
2263# none
2264
2265# TAG: sslproxy_cert_sign_hash
2266# Note: This option is only available if Squid is rebuilt with the
2267# --with-openssl
2268#
2269# Sets the hashing algorithm to use when signing generated certificates.
2270# Valid algorithm names depend on the OpenSSL library used. The following
2271# names are usually available: sha1, sha256, sha512, and md5. Please see
2272# your OpenSSL library manual for the available hashes. By default, Squids
2273# that support this option use sha256 hashes.
2274#
2275# Squid does not forcefully purge cached certificates that were generated
2276# with an algorithm other than the currently configured one. They remain
2277# in the cache, subject to the regular cache eviction policy, and become
2278# useful if the algorithm changes again.
2279#Default:
2280# none
2281
2282# TAG: ssl_bump
2283# Note: This option is only available if Squid is rebuilt with the
2284# --with-openssl
2285#
2286# This option is consulted when a CONNECT request is received on
2287# an http_port (or a new connection is intercepted at an
2288# https_port), provided that port was configured with an ssl-bump
2289# flag. The subsequent data on the connection is either treated as
2290# HTTPS and decrypted OR tunneled at TCP level without decryption,
2291# depending on the first matching bumping "action".
2292#
2293# ssl_bump <action> [!]acl ...
2294#
2295# The following bumping actions are currently supported:
2296#
2297# splice
2298# Become a TCP tunnel without decrypting proxied traffic.
2299# This is the default action.
2300#
2301# bump
2302# When used on step SslBump1, establishes a secure connection
2303# with the client first, then connect to the server.
2304# When used on step SslBump2 or SslBump3, establishes a secure
2305# connection with the server and, using a mimicked server
2306# certificate, with the client.
2307#
2308# peek
2309# Receive client (step SslBump1) or server (step SslBump2)
2310# certificate while preserving the possibility of splicing the
2311# connection. Peeking at the server certificate (during step 2)
2312# usually precludes bumping of the connection at step 3.
2313#
2314# stare
2315# Receive client (step SslBump1) or server (step SslBump2)
2316# certificate while preserving the possibility of bumping the
2317# connection. Staring at the server certificate (during step 2)
2318# usually precludes splicing of the connection at step 3.
2319#
2320# terminate
2321# Close client and server connections.
2322#
2323# Backward compatibility actions available at step SslBump1:
2324#
2325# client-first
2326# Bump the connection. Establish a secure connection with the
2327# client first, then connect to the server. This old mode does
2328# not allow Squid to mimic server SSL certificate and does not
2329# work with intercepted SSL connections.
2330#
2331# server-first
2332# Bump the connection. Establish a secure connection with the
2333# server first, then establish a secure connection with the
2334# client, using a mimicked server certificate. Works with both
2335# CONNECT requests and intercepted SSL connections, but does
2336# not allow to make decisions based on SSL handshake info.
2337#
2338# peek-and-splice
2339# Decide whether to bump or splice the connection based on
2340# client-to-squid and server-to-squid SSL hello messages.
2341# XXX: Remove.
2342#
2343# none
2344# Same as the "splice" action.
2345#
2346# All ssl_bump rules are evaluated at each of the supported bumping
2347# steps. Rules with actions that are impossible at the current step are
2348# ignored. The first matching ssl_bump action wins and is applied at the
2349# end of the current step. If no rules match, the splice action is used.
2350# See the at_step ACL for a list of the supported SslBump steps.
2351#
2352# This clause supports both fast and slow acl types.
2353# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
2354#
2355# See also: http_port ssl-bump, https_port ssl-bump, and acl at_step.
2356#
2357#
2358# # Example: Bump all TLS connections except those originating from
2359# # localhost or those going to example.com.
2360#
2361# acl broken_sites ssl::server_name .example.com
2362# ssl_bump splice localhost
2363# ssl_bump splice broken_sites
2364# ssl_bump bump all
2365#Default:
2366# Become a TCP tunnel without decrypting proxied traffic.
2367
2368# TAG: sslproxy_flags
2369# Note: This option is only available if Squid is rebuilt with the
2370# --with-openssl
2371#
2372# Various flags modifying the use of SSL while proxying https:// URLs:
2373# DONT_VERIFY_PEER Accept certificates that fail verification.
2374# For refined control, see sslproxy_cert_error.
2375# NO_DEFAULT_CA Don't use the default CA list built in
2376# to OpenSSL.
2377#Default:
2378# none
2379
2380# TAG: sslproxy_cert_error
2381# Note: This option is only available if Squid is rebuilt with the
2382# --with-openssl
2383#
2384# Use this ACL to bypass server certificate validation errors.
2385#
2386# For example, the following lines will bypass all validation errors
2387# when talking to servers for example.com. All other
2388# validation errors will result in ERR_SECURE_CONNECT_FAIL error.
2389#
2390# acl BrokenButTrustedServers dstdomain example.com
2391# sslproxy_cert_error allow BrokenButTrustedServers
2392# sslproxy_cert_error deny all
2393#
2394# This clause only supports fast acl types.
2395# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
2396# Using slow acl types may result in server crashes
2397#
2398# Without this option, all server certificate validation errors
2399# terminate the transaction to protect Squid and the client.
2400#
2401# SQUID_X509_V_ERR_INFINITE_VALIDATION error cannot be bypassed
2402# but should not happen unless your OpenSSL library is buggy.
2403#
2404# SECURITY WARNING:
2405# Bypassing validation errors is dangerous because an
2406# error usually implies that the server cannot be trusted
2407# and the connection may be insecure.
2408#
2409# See also: sslproxy_flags and DONT_VERIFY_PEER.
2410#Default:
2411# Server certificate errors terminate the transaction.
2412
2413# TAG: sslproxy_cert_sign
2414# Note: This option is only available if Squid is rebuilt with the
2415# --with-openssl
2416#
2417#
2418# sslproxy_cert_sign <signing algorithm> acl ...
2419#
2420# The following certificate signing algorithms are supported:
2421#
2422# signTrusted
2423# Sign using the configured CA certificate which is usually
2424# placed in and trusted by end-user browsers. This is the
2425# default for trusted origin server certificates.
2426#
2427# signUntrusted
2428# Sign to guarantee an X509_V_ERR_CERT_UNTRUSTED browser error.
2429# This is the default for untrusted origin server certificates
2430# that are not self-signed (see ssl::certUntrusted).
2431#
2432# signSelf
2433# Sign using a self-signed certificate with the right CN to
2434# generate a X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT error in the
2435# browser. This is the default for self-signed origin server
2436# certificates (see ssl::certSelfSigned).
2437#
2438# This clause only supports fast acl types.
2439#
2440# When sslproxy_cert_sign acl(s) match, Squid uses the corresponding
2441# signing algorithm to generate the certificate and ignores all
2442# subsequent sslproxy_cert_sign options (the first match wins). If no
2443# acl(s) match, the default signing algorithm is determined by errors
2444# detected when obtaining and validating the origin server certificate.
2445#
2446# WARNING: SQUID_X509_V_ERR_DOMAIN_MISMATCH and ssl:certDomainMismatch can
2447# be used with sslproxy_cert_adapt, but if and only if Squid is bumping a
2448# CONNECT request that carries a domain name. In all other cases (CONNECT
2449# to an IP address or an intercepted SSL connection), Squid cannot detect
2450# the domain mismatch at certificate generation time when
2451# bump-server-first is used.
2452#Default:
2453# none
2454
2455# TAG: sslproxy_cert_adapt
2456# Note: This option is only available if Squid is rebuilt with the
2457# --with-openssl
2458#
2459#
2460# sslproxy_cert_adapt <adaptation algorithm> acl ...
2461#
2462# The following certificate adaptation algorithms are supported:
2463#
2464# setValidAfter
2465# Sets the "Not After" property to the "Not After" property of
2466# the CA certificate used to sign generated certificates.
2467#
2468# setValidBefore
2469# Sets the "Not Before" property to the "Not Before" property of
2470# the CA certificate used to sign generated certificates.
2471#
2472# setCommonName or setCommonName{CN}
2473# Sets Subject.CN property to the host name specified as a
2474# CN parameter or, if no explicit CN parameter was specified,
2475# extracted from the CONNECT request. It is a misconfiguration
2476# to use setCommonName without an explicit parameter for
2477# intercepted or tproxied SSL connections.
2478#
2479# This clause only supports fast acl types.
2480#
2481# Squid first groups sslproxy_cert_adapt options by adaptation algorithm.
2482# Within a group, when sslproxy_cert_adapt acl(s) match, Squid uses the
2483# corresponding adaptation algorithm to generate the certificate and
2484# ignores all subsequent sslproxy_cert_adapt options in that algorithm's
2485# group (i.e., the first match wins within each algorithm group). If no
2486# acl(s) match, the default mimicking action takes place.
2487#
2488# WARNING: SQUID_X509_V_ERR_DOMAIN_MISMATCH and ssl:certDomainMismatch can
2489# be used with sslproxy_cert_adapt, but if and only if Squid is bumping a
2490# CONNECT request that carries a domain name. In all other cases (CONNECT
2491# to an IP address or an intercepted SSL connection), Squid cannot detect
2492# the domain mismatch at certificate generation time when
2493# bump-server-first is used.
2494#Default:
2495# none
2496
2497# TAG: sslpassword_program
2498# Note: This option is only available if Squid is rebuilt with the
2499# --with-openssl
2500#
2501# Specify a program used for entering SSL key passphrases
2502# when using encrypted SSL certificate keys. If not specified
2503# keys must either be unencrypted, or Squid started with the -N
2504# option to allow it to query interactively for the passphrase.
2505#
2506# The key file name is given as argument to the program allowing
2507# selection of the right password if you have multiple encrypted
2508# keys.
2509#Default:
2510# none
2511
2512# OPTIONS RELATING TO EXTERNAL SSL_CRTD
2513# -----------------------------------------------------------------------------
2514
2515# TAG: sslcrtd_program
2516# Note: This option is only available if Squid is rebuilt with the
2517# --enable-ssl-crtd
2518#
2519# Specify the location and options of the executable for ssl_crtd process.
2520# /usr/lib/squid/ssl_crtd program requires -s and -M parameters
2521# For more information use:
2522# /usr/lib/squid/ssl_crtd -h
2523#Default:
2524# sslcrtd_program /usr/lib/squid/ssl_crtd -s /var/lib/ssl_db -M 4MB
2525
2526# TAG: sslcrtd_children
2527# Note: This option is only available if Squid is rebuilt with the
2528# --enable-ssl-crtd
2529#
2530# The maximum number of processes spawn to service ssl server.
2531# The maximum this may be safely set to is 32.
2532#
2533# The startup= and idle= options allow some measure of skew in your
2534# tuning.
2535#
2536# startup=N
2537#
2538# Sets the minimum number of processes to spawn when Squid
2539# starts or reconfigures. When set to zero the first request will
2540# cause spawning of the first child process to handle it.
2541#
2542# Starting too few children temporary slows Squid under load while it
2543# tries to spawn enough additional processes to cope with traffic.
2544#
2545# idle=N
2546#
2547# Sets a minimum of how many processes Squid is to try and keep available
2548# at all times. When traffic begins to rise above what the existing
2549# processes can handle this many more will be spawned up to the maximum
2550# configured. A minimum setting of 1 is required.
2551#
2552# You must have at least one ssl_crtd process.
2553#Default:
2554# sslcrtd_children 32 startup=5 idle=1
2555
2556# TAG: sslcrtvalidator_program
2557# Note: This option is only available if Squid is rebuilt with the
2558# --with-openssl
2559#
2560# Specify the location and options of the executable for ssl_crt_validator
2561# process.
2562#
2563# Usage: sslcrtvalidator_program [ttl=n] [cache=n] path ...
2564#
2565# Options:
2566# ttl=n TTL in seconds for cached results. The default is 60 secs
2567# cache=n limit the result cache size. The default value is 2048
2568#Default:
2569# none
2570
2571# TAG: sslcrtvalidator_children
2572# Note: This option is only available if Squid is rebuilt with the
2573# --with-openssl
2574#
2575# The maximum number of processes spawn to service SSL server.
2576# The maximum this may be safely set to is 32.
2577#
2578# The startup= and idle= options allow some measure of skew in your
2579# tuning.
2580#
2581# startup=N
2582#
2583# Sets the minimum number of processes to spawn when Squid
2584# starts or reconfigures. When set to zero the first request will
2585# cause spawning of the first child process to handle it.
2586#
2587# Starting too few children temporary slows Squid under load while it
2588# tries to spawn enough additional processes to cope with traffic.
2589#
2590# idle=N
2591#
2592# Sets a minimum of how many processes Squid is to try and keep available
2593# at all times. When traffic begins to rise above what the existing
2594# processes can handle this many more will be spawned up to the maximum
2595# configured. A minimum setting of 1 is required.
2596#
2597# concurrency=
2598#
2599# The number of requests each certificate validator helper can handle in
2600# parallel. A value of 0 indicates the certficate validator does not
2601# support concurrency. Defaults to 1.
2602#
2603# When this directive is set to a value >= 1 then the protocol
2604# used to communicate with the helper is modified to include
2605# a request ID in front of the request/response. The request
2606# ID from the request must be echoed back with the response
2607# to that request.
2608#
2609# You must have at least one ssl_crt_validator process.
2610#Default:
2611# sslcrtvalidator_children 32 startup=5 idle=1 concurrency=1
2612
2613# OPTIONS WHICH AFFECT THE NEIGHBOR SELECTION ALGORITHM
2614# -----------------------------------------------------------------------------
2615
2616# TAG: cache_peer
2617# To specify other caches in a hierarchy, use the format:
2618#
2619# cache_peer hostname type http-port icp-port [options]
2620#
2621# For example,
2622#
2623# # proxy icp
2624# # hostname type port port options
2625# # -------------------- -------- ----- ----- -----------
2626# cache_peer parent.foo.net parent 3128 3130 default
2627# cache_peer sib1.foo.net sibling 3128 3130 proxy-only
2628# cache_peer sib2.foo.net sibling 3128 3130 proxy-only
2629# cache_peer example.com parent 80 0 default
2630# cache_peer cdn.example.com sibling 3128 0
2631#
2632# type: either 'parent', 'sibling', or 'multicast'.
2633#
2634# proxy-port: The port number where the peer accept HTTP requests.
2635# For other Squid proxies this is usually 3128
2636# For web servers this is usually 80
2637#
2638# icp-port: Used for querying neighbor caches about objects.
2639# Set to 0 if the peer does not support ICP or HTCP.
2640# See ICP and HTCP options below for additional details.
2641#
2642#
2643# ==== ICP OPTIONS ====
2644#
2645# You MUST also set icp_port and icp_access explicitly when using these options.
2646# The defaults will prevent peer traffic using ICP.
2647#
2648#
2649# no-query Disable ICP queries to this neighbor.
2650#
2651# multicast-responder
2652# Indicates the named peer is a member of a multicast group.
2653# ICP queries will not be sent directly to the peer, but ICP
2654# replies will be accepted from it.
2655#
2656# closest-only Indicates that, for ICP_OP_MISS replies, we'll only forward
2657# CLOSEST_PARENT_MISSes and never FIRST_PARENT_MISSes.
2658#
2659# background-ping
2660# To only send ICP queries to this neighbor infrequently.
2661# This is used to keep the neighbor round trip time updated
2662# and is usually used in conjunction with weighted-round-robin.
2663#
2664#
2665# ==== HTCP OPTIONS ====
2666#
2667# You MUST also set htcp_port and htcp_access explicitly when using these options.
2668# The defaults will prevent peer traffic using HTCP.
2669#
2670#
2671# htcp Send HTCP, instead of ICP, queries to the neighbor.
2672# You probably also want to set the "icp-port" to 4827
2673# instead of 3130. This directive accepts a comma separated
2674# list of options described below.
2675#
2676# htcp=oldsquid Send HTCP to old Squid versions (2.5 or earlier).
2677#
2678# htcp=no-clr Send HTCP to the neighbor but without
2679# sending any CLR requests. This cannot be used with
2680# only-clr.
2681#
2682# htcp=only-clr Send HTCP to the neighbor but ONLY CLR requests.
2683# This cannot be used with no-clr.
2684#
2685# htcp=no-purge-clr
2686# Send HTCP to the neighbor including CLRs but only when
2687# they do not result from PURGE requests.
2688#
2689# htcp=forward-clr
2690# Forward any HTCP CLR requests this proxy receives to the peer.
2691#
2692#
2693# ==== PEER SELECTION METHODS ====
2694#
2695# The default peer selection method is ICP, with the first responding peer
2696# being used as source. These options can be used for better load balancing.
2697#
2698#
2699# default This is a parent cache which can be used as a "last-resort"
2700# if a peer cannot be located by any of the peer-selection methods.
2701# If specified more than once, only the first is used.
2702#
2703# round-robin Load-Balance parents which should be used in a round-robin
2704# fashion in the absence of any ICP queries.
2705# weight=N can be used to add bias.
2706#
2707# weighted-round-robin
2708# Load-Balance parents which should be used in a round-robin
2709# fashion with the frequency of each parent being based on the
2710# round trip time. Closer parents are used more often.
2711# Usually used for background-ping parents.
2712# weight=N can be used to add bias.
2713#
2714# carp Load-Balance parents which should be used as a CARP array.
2715# The requests will be distributed among the parents based on the
2716# CARP load balancing hash function based on their weight.
2717#
2718# userhash Load-balance parents based on the client proxy_auth or ident username.
2719#
2720# sourcehash Load-balance parents based on the client source IP.
2721#
2722# multicast-siblings
2723# To be used only for cache peers of type "multicast".
2724# ALL members of this multicast group have "sibling"
2725# relationship with it, not "parent". This is to a multicast
2726# group when the requested object would be fetched only from
2727# a "parent" cache, anyway. It's useful, e.g., when
2728# configuring a pool of redundant Squid proxies, being
2729# members of the same multicast group.
2730#
2731#
2732# ==== PEER SELECTION OPTIONS ====
2733#
2734# weight=N use to affect the selection of a peer during any weighted
2735# peer-selection mechanisms.
2736# The weight must be an integer; default is 1,
2737# larger weights are favored more.
2738# This option does not affect parent selection if a peering
2739# protocol is not in use.
2740#
2741# basetime=N Specify a base amount to be subtracted from round trip
2742# times of parents.
2743# It is subtracted before division by weight in calculating
2744# which parent to fectch from. If the rtt is less than the
2745# base time the rtt is set to a minimal value.
2746#
2747# ttl=N Specify a TTL to use when sending multicast ICP queries
2748# to this address.
2749# Only useful when sending to a multicast group.
2750# Because we don't accept ICP replies from random
2751# hosts, you must configure other group members as
2752# peers with the 'multicast-responder' option.
2753#
2754# no-delay To prevent access to this neighbor from influencing the
2755# delay pools.
2756#
2757# digest-url=URL Tell Squid to fetch the cache digest (if digests are
2758# enabled) for this host from the specified URL rather
2759# than the Squid default location.
2760#
2761#
2762# ==== CARP OPTIONS ====
2763#
2764# carp-key=key-specification
2765# use a different key than the full URL to hash against the peer.
2766# the key-specification is a comma-separated list of the keywords
2767# scheme, host, port, path, params
2768# Order is not important.
2769#
2770# ==== ACCELERATOR / REVERSE-PROXY OPTIONS ====
2771#
2772# originserver Causes this parent to be contacted as an origin server.
2773# Meant to be used in accelerator setups when the peer
2774# is a web server.
2775#
2776# forceddomain=name
2777# Set the Host header of requests forwarded to this peer.
2778# Useful in accelerator setups where the server (peer)
2779# expects a certain domain name but clients may request
2780# others. ie example.com or www.example.com
2781#
2782# no-digest Disable request of cache digests.
2783#
2784# no-netdb-exchange
2785# Disables requesting ICMP RTT database (NetDB).
2786#
2787#
2788# ==== AUTHENTICATION OPTIONS ====
2789#
2790# login=user:password
2791# If this is a personal/workgroup proxy and your parent
2792# requires proxy authentication.
2793#
2794# Note: The string can include URL escapes (i.e. %20 for
2795# spaces). This also means % must be written as %%.
2796#
2797# login=PASSTHRU
2798# Send login details received from client to this peer.
2799# Both Proxy- and WWW-Authorization headers are passed
2800# without alteration to the peer.
2801# Authentication is not required by Squid for this to work.
2802#
2803# Note: This will pass any form of authentication but
2804# only Basic auth will work through a proxy unless the
2805# connection-auth options are also used.
2806#
2807# login=PASS Send login details received from client to this peer.
2808# Authentication is not required by this option.
2809#
2810# If there are no client-provided authentication headers
2811# to pass on, but username and password are available
2812# from an external ACL user= and password= result tags
2813# they may be sent instead.
2814#
2815# Note: To combine this with proxy_auth both proxies must
2816# share the same user database as HTTP only allows for
2817# a single login (one for proxy, one for origin server).
2818# Also be warned this will expose your users proxy
2819# password to the peer. USE WITH CAUTION
2820#
2821# login=*:password
2822# Send the username to the upstream cache, but with a
2823# fixed password. This is meant to be used when the peer
2824# is in another administrative domain, but it is still
2825# needed to identify each user.
2826# The star can optionally be followed by some extra
2827# information which is added to the username. This can
2828# be used to identify this proxy to the peer, similar to
2829# the login=username:password option above.
2830#
2831# login=NEGOTIATE
2832# If this is a personal/workgroup proxy and your parent
2833# requires a secure proxy authentication.
2834# The first principal from the default keytab or defined by
2835# the environment variable KRB5_KTNAME will be used.
2836#
2837# WARNING: The connection may transmit requests from multiple
2838# clients. Negotiate often assumes end-to-end authentication
2839# and a single-client. Which is not strictly true here.
2840#
2841# login=NEGOTIATE:principal_name
2842# If this is a personal/workgroup proxy and your parent
2843# requires a secure proxy authentication.
2844# The principal principal_name from the default keytab or
2845# defined by the environment variable KRB5_KTNAME will be
2846# used.
2847#
2848# WARNING: The connection may transmit requests from multiple
2849# clients. Negotiate often assumes end-to-end authentication
2850# and a single-client. Which is not strictly true here.
2851#
2852# connection-auth=on|off
2853# Tell Squid that this peer does or not support Microsoft
2854# connection oriented authentication, and any such
2855# challenges received from there should be ignored.
2856# Default is auto to automatically determine the status
2857# of the peer.
2858#
2859#
2860# ==== SSL / HTTPS / TLS OPTIONS ====
2861#
2862# ssl Encrypt connections to this peer with SSL/TLS.
2863#
2864# sslcert=/path/to/ssl/certificate
2865# A client SSL certificate to use when connecting to
2866# this peer.
2867#
2868# sslkey=/path/to/ssl/key
2869# The private SSL key corresponding to sslcert above.
2870# If 'sslkey' is not specified 'sslcert' is assumed to
2871# reference a combined file containing both the
2872# certificate and the key.
2873#
2874# Notes:
2875#
2876# On Debian/Ubuntu systems a default snakeoil certificate is
2877# available in /etc/ssl and users can set:
2878#
2879# cert=/etc/ssl/certs/ssl-cert-snakeoil.pem
2880#
2881# and
2882#
2883# key=/etc/ssl/private/ssl-cert-snakeoil.key
2884#
2885# for testing.
2886#
2887# sslversion=1|2|3|4|5|6
2888# The SSL version to use when connecting to this peer
2889# 1 = automatic (default)
2890# 2 = SSL v2 only
2891# 3 = SSL v3 only
2892# 4 = TLS v1.0 only
2893# 5 = TLS v1.1 only
2894# 6 = TLS v1.2 only
2895#
2896# sslcipher=... The list of valid SSL ciphers to use when connecting
2897# to this peer.
2898#
2899# ssloptions=... Specify various SSL implementation options:
2900#
2901# NO_SSLv2 Disallow the use of SSLv2
2902# NO_SSLv3 Disallow the use of SSLv3
2903# NO_TLSv1 Disallow the use of TLSv1.0
2904# NO_TLSv1_1 Disallow the use of TLSv1.1
2905# NO_TLSv1_2 Disallow the use of TLSv1.2
2906#
2907# SINGLE_DH_USE
2908# Always create a new key when using
2909# temporary/ephemeral DH key exchanges
2910#
2911# NO_TICKET
2912# Disable use of RFC5077 session tickets. Some servers
2913# may have problems understanding the TLS extension due
2914# to ambiguous specification in RFC4507.
2915#
2916# ALL Enable various bug workarounds
2917# suggested as "harmless" by OpenSSL
2918# Be warned that this reduces SSL/TLS
2919# strength to some attacks.
2920#
2921# See the OpenSSL SSL_CTX_set_options documentation for a
2922# more complete list.
2923#
2924# sslcafile=... A file containing additional CA certificates to use
2925# when verifying the peer certificate.
2926#
2927# sslcapath=... A directory containing additional CA certificates to
2928# use when verifying the peer certificate.
2929#
2930# sslcrlfile=... A certificate revocation list file to use when
2931# verifying the peer certificate.
2932#
2933# sslflags=... Specify various flags modifying the SSL implementation:
2934#
2935# DONT_VERIFY_PEER
2936# Accept certificates even if they fail to
2937# verify.
2938# NO_DEFAULT_CA
2939# Don't use the default CA list built in
2940# to OpenSSL.
2941# DONT_VERIFY_DOMAIN
2942# Don't verify the peer certificate
2943# matches the server name
2944#
2945# ssldomain= The peer name as advertised in it's certificate.
2946# Used for verifying the correctness of the received peer
2947# certificate. If not specified the peer hostname will be
2948# used.
2949#
2950# front-end-https
2951# Enable the "Front-End-Https: On" header needed when
2952# using Squid as a SSL frontend in front of Microsoft OWA.
2953# See MS KB document Q307347 for details on this header.
2954# If set to auto the header will only be added if the
2955# request is forwarded as a https:// URL.
2956#
2957#
2958# ==== GENERAL OPTIONS ====
2959#
2960# connect-timeout=N
2961# A peer-specific connect timeout.
2962# Also see the peer_connect_timeout directive.
2963#
2964# connect-fail-limit=N
2965# How many times connecting to a peer must fail before
2966# it is marked as down. Standby connection failures
2967# count towards this limit. Default is 10.
2968#
2969# allow-miss Disable Squid's use of only-if-cached when forwarding
2970# requests to siblings. This is primarily useful when
2971# icp_hit_stale is used by the sibling. Excessive use
2972# of this option may result in forwarding loops. One way
2973# to prevent peering loops when using this option, is to
2974# deny cache peer usage on requests from a peer:
2975# acl fromPeer ...
2976# cache_peer_access peerName deny fromPeer
2977#
2978# max-conn=N Limit the number of concurrent connections the Squid
2979# may open to this peer, including already opened idle
2980# and standby connections. There is no peer-specific
2981# connection limit by default.
2982#
2983# A peer exceeding the limit is not used for new
2984# requests unless a standby connection is available.
2985#
2986# max-conn currently works poorly with idle persistent
2987# connections: When a peer reaches its max-conn limit,
2988# and there are idle persistent connections to the peer,
2989# the peer may not be selected because the limiting code
2990# does not know whether Squid can reuse those idle
2991# connections.
2992#
2993# standby=N Maintain a pool of N "hot standby" connections to an
2994# UP peer, available for requests when no idle
2995# persistent connection is available (or safe) to use.
2996# By default and with zero N, no such pool is maintained.
2997# N must not exceed the max-conn limit (if any).
2998#
2999# At start or after reconfiguration, Squid opens new TCP
3000# standby connections until there are N connections
3001# available and then replenishes the standby pool as
3002# opened connections are used up for requests. A used
3003# connection never goes back to the standby pool, but
3004# may go to the regular idle persistent connection pool
3005# shared by all peers and origin servers.
3006#
3007# Squid never opens multiple new standby connections
3008# concurrently. This one-at-a-time approach minimizes
3009# flooding-like effect on peers. Furthermore, just a few
3010# standby connections should be sufficient in most cases
3011# to supply most new requests with a ready-to-use
3012# connection.
3013#
3014# Standby connections obey server_idle_pconn_timeout.
3015# For the feature to work as intended, the peer must be
3016# configured to accept and keep them open longer than
3017# the idle timeout at the connecting Squid, to minimize
3018# race conditions typical to idle used persistent
3019# connections. Default request_timeout and
3020# server_idle_pconn_timeout values ensure such a
3021# configuration.
3022#
3023# name=xxx Unique name for the peer.
3024# Required if you have multiple peers on the same host
3025# but different ports.
3026# This name can be used in cache_peer_access and similar
3027# directives to identify the peer.
3028# Can be used by outgoing access controls through the
3029# peername ACL type.
3030#
3031# no-tproxy Do not use the client-spoof TPROXY support when forwarding
3032# requests to this peer. Use normal address selection instead.
3033# This overrides the spoof_client_ip ACL.
3034#
3035# proxy-only objects fetched from the peer will not be stored locally.
3036#
3037#Default:
3038# none
3039
3040# TAG: cache_peer_domain
3041# Use to limit the domains for which a neighbor cache will be
3042# queried.
3043#
3044# Usage:
3045# cache_peer_domain cache-host domain [domain ...]
3046# cache_peer_domain cache-host !domain
3047#
3048# For example, specifying
3049#
3050# cache_peer_domain parent.foo.net .edu
3051#
3052# has the effect such that UDP query packets are sent to
3053# 'bigserver' only when the requested object exists on a
3054# server in the .edu domain. Prefixing the domainname
3055# with '!' means the cache will be queried for objects
3056# NOT in that domain.
3057#
3058# NOTE: * Any number of domains may be given for a cache-host,
3059# either on the same or separate lines.
3060# * When multiple domains are given for a particular
3061# cache-host, the first matched domain is applied.
3062# * Cache hosts with no domain restrictions are queried
3063# for all requests.
3064# * There are no defaults.
3065# * There is also a 'cache_peer_access' tag in the ACL
3066# section.
3067#Default:
3068# none
3069
3070# TAG: cache_peer_access
3071# Restricts usage of cache_peer proxies.
3072#
3073# Usage:
3074# cache_peer_access peer-name allow|deny [!]aclname ...
3075#
3076# For the required peer-name parameter, use either the value of the
3077# cache_peer name=value parameter or, if name=value is missing, the
3078# cache_peer hostname parameter.
3079#
3080# This directive narrows down the selection of peering candidates, but
3081# does not determine the order in which the selected candidates are
3082# contacted. That order is determined by the peer selection algorithms
3083# (see PEER SELECTION sections in the cache_peer documentation).
3084#
3085# If a deny rule matches, the corresponding peer will not be contacted
3086# for the current transaction -- Squid will not send ICP queries and
3087# will not forward HTTP requests to that peer. An allow match leaves
3088# the corresponding peer in the selection. The first match for a given
3089# peer wins for that peer.
3090#
3091# The relative order of cache_peer_access directives for the same peer
3092# matters. The relative order of any two cache_peer_access directives
3093# for different peers does not matter. To ease interpretation, it is a
3094# good idea to group cache_peer_access directives for the same peer
3095# together.
3096#
3097# A single cache_peer_access directive may be evaluated multiple times
3098# for a given transaction because individual peer selection algorithms
3099# may check it independently from each other. These redundant checks
3100# may be optimized away in future Squid versions.
3101#
3102# This clause only supports fast acl types.
3103# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
3104#Default:
3105# No peer usage restrictions.
3106
3107# TAG: neighbor_type_domain
3108# Modify the cache_peer neighbor type when passing requests
3109# about specific domains to the peer.
3110#
3111# Usage:
3112# neighbor_type_domain neighbor parent|sibling domain domain ...
3113#
3114# For example:
3115# cache_peer foo.example.com parent 3128 3130
3116# neighbor_type_domain foo.example.com sibling .au .de
3117#
3118# The above configuration treats all requests to foo.example.com as a
3119# parent proxy unless the request is for a .au or .de ccTLD domain name.
3120#Default:
3121# The peer type from cache_peer directive is used for all requests to that peer.
3122
3123# TAG: dead_peer_timeout (seconds)
3124# This controls how long Squid waits to declare a peer cache
3125# as "dead." If there are no ICP replies received in this
3126# amount of time, Squid will declare the peer dead and not
3127# expect to receive any further ICP replies. However, it
3128# continues to send ICP queries, and will mark the peer as
3129# alive upon receipt of the first subsequent ICP reply.
3130#
3131# This timeout also affects when Squid expects to receive ICP
3132# replies from peers. If more than 'dead_peer' seconds have
3133# passed since the last ICP reply was received, Squid will not
3134# expect to receive an ICP reply on the next query. Thus, if
3135# your time between requests is greater than this timeout, you
3136# will see a lot of requests sent DIRECT to origin servers
3137# instead of to your parents.
3138#Default:
3139# dead_peer_timeout 10 seconds
3140
3141# TAG: forward_max_tries
3142# Controls how many different forward paths Squid will try
3143# before giving up. See also forward_timeout.
3144#
3145# NOTE: connect_retries (default: none) can make each of these
3146# possible forwarding paths be tried multiple times.
3147#Default:
3148# forward_max_tries 25
3149
3150# MEMORY CACHE OPTIONS
3151# -----------------------------------------------------------------------------
3152
3153# TAG: cache_mem (bytes)
3154# NOTE: THIS PARAMETER DOES NOT SPECIFY THE MAXIMUM PROCESS SIZE.
3155# IT ONLY PLACES A LIMIT ON HOW MUCH ADDITIONAL MEMORY SQUID WILL
3156# USE AS A MEMORY CACHE OF OBJECTS. SQUID USES MEMORY FOR OTHER
3157# THINGS AS WELL. SEE THE SQUID FAQ SECTION 8 FOR DETAILS.
3158#
3159# 'cache_mem' specifies the ideal amount of memory to be used
3160# for:
3161# * In-Transit objects
3162# * Hot Objects
3163# * Negative-Cached objects
3164#
3165# Data for these objects are stored in 4 KB blocks. This
3166# parameter specifies the ideal upper limit on the total size of
3167# 4 KB blocks allocated. In-Transit objects take the highest
3168# priority.
3169#
3170# In-transit objects have priority over the others. When
3171# additional space is needed for incoming data, negative-cached
3172# and hot objects will be released. In other words, the
3173# negative-cached and hot objects will fill up any unused space
3174# not needed for in-transit objects.
3175#
3176# If circumstances require, this limit will be exceeded.
3177# Specifically, if your incoming request rate requires more than
3178# 'cache_mem' of memory to hold in-transit objects, Squid will
3179# exceed this limit to satisfy the new requests. When the load
3180# decreases, blocks will be freed until the high-water mark is
3181# reached. Thereafter, blocks will be used to store hot
3182# objects.
3183#
3184# If shared memory caching is enabled, Squid does not use the shared
3185# cache space for in-transit objects, but they still consume as much
3186# local memory as they need. For more details about the shared memory
3187# cache, see memory_cache_shared.
3188#Default:
3189# cache_mem 256 MB
3190
3191# TAG: maximum_object_size_in_memory (bytes)
3192# Objects greater than this size will not be attempted to kept in
3193# the memory cache. This should be set high enough to keep objects
3194# accessed frequently in memory to improve performance whilst low
3195# enough to keep larger objects from hoarding cache_mem.
3196#Default:
3197# maximum_object_size_in_memory 512 KB
3198
3199# TAG: memory_cache_shared on|off
3200# Controls whether the memory cache is shared among SMP workers.
3201#
3202# The shared memory cache is meant to occupy cache_mem bytes and replace
3203# the non-shared memory cache, although some entities may still be
3204# cached locally by workers for now (e.g., internal and in-transit
3205# objects may be served from a local memory cache even if shared memory
3206# caching is enabled).
3207#
3208# By default, the memory cache is shared if and only if all of the
3209# following conditions are satisfied: Squid runs in SMP mode with
3210# multiple workers, cache_mem is positive, and Squid environment
3211# supports required IPC primitives (e.g., POSIX shared memory segments
3212# and GCC-style atomic operations).
3213#
3214# To avoid blocking locks, shared memory uses opportunistic algorithms
3215# that do not guarantee that every cachable entity that could have been
3216# shared among SMP workers will actually be shared.
3217#Default:
3218# "on" where supported if doing memory caching with multiple SMP workers.
3219
3220# TAG: memory_cache_mode
3221# Controls which objects to keep in the memory cache (cache_mem)
3222#
3223# always Keep most recently fetched objects in memory (default)
3224#
3225# disk Only disk cache hits are kept in memory, which means
3226# an object must first be cached on disk and then hit
3227# a second time before cached in memory.
3228#
3229# network Only objects fetched from network is kept in memory
3230#Default:
3231# Keep the most recently fetched objects in memory
3232
3233# TAG: memory_replacement_policy
3234# The memory replacement policy parameter determines which
3235# objects are purged from memory when memory space is needed.
3236#
3237# See cache_replacement_policy for details on algorithms.
3238#Default:
3239# memory_replacement_policy lru
3240
3241# DISK CACHE OPTIONS
3242# -----------------------------------------------------------------------------
3243
3244# TAG: cache_replacement_policy
3245# The cache replacement policy parameter determines which
3246# objects are evicted (replaced) when disk space is needed.
3247#
3248# lru : Squid's original list based LRU policy
3249# heap GDSF : Greedy-Dual Size Frequency
3250# heap LFUDA: Least Frequently Used with Dynamic Aging
3251# heap LRU : LRU policy implemented using a heap
3252#
3253# Applies to any cache_dir lines listed below this directive.
3254#
3255# The LRU policies keeps recently referenced objects.
3256#
3257# The heap GDSF policy optimizes object hit rate by keeping smaller
3258# popular objects in cache so it has a better chance of getting a
3259# hit. It achieves a lower byte hit rate than LFUDA though since
3260# it evicts larger (possibly popular) objects.
3261#
3262# The heap LFUDA policy keeps popular objects in cache regardless of
3263# their size and thus optimizes byte hit rate at the expense of
3264# hit rate since one large, popular object will prevent many
3265# smaller, slightly less popular objects from being cached.
3266#
3267# Both policies utilize a dynamic aging mechanism that prevents
3268# cache pollution that can otherwise occur with frequency-based
3269# replacement policies.
3270#
3271# NOTE: if using the LFUDA replacement policy you should increase
3272# the value of maximum_object_size above its default of 4 MB to
3273# to maximize the potential byte hit rate improvement of LFUDA.
3274#
3275# For more information about the GDSF and LFUDA cache replacement
3276# policies see http://www.hpl.hp.com/techreports/1999/HPL-1999-69.html
3277# and http://fog.hpl.external.hp.com/techreports/98/HPL-98-173.html.
3278#Default:
3279# cache_replacement_policy lru
3280
3281# TAG: minimum_object_size (bytes)
3282# Objects smaller than this size will NOT be saved on disk. The
3283# value is specified in bytes, and the default is 0 KB, which
3284# means all responses can be stored.
3285#Default:
3286# no limit
3287
3288# TAG: maximum_object_size (bytes)
3289# Set the default value for max-size parameter on any cache_dir.
3290# The value is specified in bytes, and the default is 4 MB.
3291#
3292# If you wish to get a high BYTES hit ratio, you should probably
3293# increase this (one 32 MB object hit counts for 3200 10KB
3294# hits).
3295#
3296# If you wish to increase hit ratio more than you want to
3297# save bandwidth you should leave this low.
3298#
3299# NOTE: if using the LFUDA replacement policy you should increase
3300# this value to maximize the byte hit rate improvement of LFUDA!
3301# See cache_replacement_policy for a discussion of this policy.
3302#Default:
3303# maximum_object_size 4 MB
3304
3305# TAG: cache_dir
3306# Format:
3307# cache_dir Type Directory-Name Fs-specific-data [options]
3308#
3309# You can specify multiple cache_dir lines to spread the
3310# cache among different disk partitions.
3311#
3312# Type specifies the kind of storage system to use. Only "ufs"
3313# is built by default. To enable any of the other storage systems
3314# see the --enable-storeio configure option.
3315#
3316# 'Directory' is a top-level directory where cache swap
3317# files will be stored. If you want to use an entire disk
3318# for caching, this can be the mount-point directory.
3319# The directory must exist and be writable by the Squid
3320# process. Squid will NOT create this directory for you.
3321#
3322# In SMP configurations, cache_dir must not precede the workers option
3323# and should use configuration macros or conditionals to give each
3324# worker interested in disk caching a dedicated cache directory.
3325#
3326#
3327# ==== The ufs store type ====
3328#
3329# "ufs" is the old well-known Squid storage format that has always
3330# been there.
3331#
3332# Usage:
3333# cache_dir ufs Directory-Name Mbytes L1 L2 [options]
3334#
3335# 'Mbytes' is the amount of disk space (MB) to use under this
3336# directory. The default is 100 MB. Change this to suit your
3337# configuration. Do NOT put the size of your disk drive here.
3338# Instead, if you want Squid to use the entire disk drive,
3339# subtract 20% and use that value.
3340#
3341# 'L1' is the number of first-level subdirectories which
3342# will be created under the 'Directory'. The default is 16.
3343#
3344# 'L2' is the number of second-level subdirectories which
3345# will be created under each first-level directory. The default
3346# is 256.
3347#
3348#
3349# ==== The aufs store type ====
3350#
3351# "aufs" uses the same storage format as "ufs", utilizing
3352# POSIX-threads to avoid blocking the main Squid process on
3353# disk-I/O. This was formerly known in Squid as async-io.
3354#
3355# Usage:
3356# cache_dir aufs Directory-Name Mbytes L1 L2 [options]
3357#
3358# see argument descriptions under ufs above
3359#
3360#
3361# ==== The diskd store type ====
3362#
3363# "diskd" uses the same storage format as "ufs", utilizing a
3364# separate process to avoid blocking the main Squid process on
3365# disk-I/O.
3366#
3367# Usage:
3368# cache_dir diskd Directory-Name Mbytes L1 L2 [options] [Q1=n] [Q2=n]
3369#
3370# see argument descriptions under ufs above
3371#
3372# Q1 specifies the number of unacknowledged I/O requests when Squid
3373# stops opening new files. If this many messages are in the queues,
3374# Squid won't open new files. Default is 64
3375#
3376# Q2 specifies the number of unacknowledged messages when Squid
3377# starts blocking. If this many messages are in the queues,
3378# Squid blocks until it receives some replies. Default is 72
3379#
3380# When Q1 < Q2 (the default), the cache directory is optimized
3381# for lower response time at the expense of a decrease in hit
3382# ratio. If Q1 > Q2, the cache directory is optimized for
3383# higher hit ratio at the expense of an increase in response
3384# time.
3385#
3386#
3387# ==== The rock store type ====
3388#
3389# Usage:
3390# cache_dir rock Directory-Name Mbytes [options]
3391#
3392# The Rock Store type is a database-style storage. All cached
3393# entries are stored in a "database" file, using fixed-size slots.
3394# A single entry occupies one or more slots.
3395#
3396# If possible, Squid using Rock Store creates a dedicated kid
3397# process called "disker" to avoid blocking Squid worker(s) on disk
3398# I/O. One disker kid is created for each rock cache_dir. Diskers
3399# are created only when Squid, running in daemon mode, has support
3400# for the IpcIo disk I/O module.
3401#
3402# swap-timeout=msec: Squid will not start writing a miss to or
3403# reading a hit from disk if it estimates that the swap operation
3404# will take more than the specified number of milliseconds. By
3405# default and when set to zero, disables the disk I/O time limit
3406# enforcement. Ignored when using blocking I/O module because
3407# blocking synchronous I/O does not allow Squid to estimate the
3408# expected swap wait time.
3409#
3410# max-swap-rate=swaps/sec: Artificially limits disk access using
3411# the specified I/O rate limit. Swap out requests that
3412# would cause the average I/O rate to exceed the limit are
3413# delayed. Individual swap in requests (i.e., hits or reads) are
3414# not delayed, but they do contribute to measured swap rate and
3415# since they are placed in the same FIFO queue as swap out
3416# requests, they may wait longer if max-swap-rate is smaller.
3417# This is necessary on file systems that buffer "too
3418# many" writes and then start blocking Squid and other processes
3419# while committing those writes to disk. Usually used together
3420# with swap-timeout to avoid excessive delays and queue overflows
3421# when disk demand exceeds available disk "bandwidth". By default
3422# and when set to zero, disables the disk I/O rate limit
3423# enforcement. Currently supported by IpcIo module only.
3424#
3425# slot-size=bytes: The size of a database "record" used for
3426# storing cached responses. A cached response occupies at least
3427# one slot and all database I/O is done using individual slots so
3428# increasing this parameter leads to more disk space waste while
3429# decreasing it leads to more disk I/O overheads. Should be a
3430# multiple of your operating system I/O page size. Defaults to
3431# 16KBytes. A housekeeping header is stored with each slot and
3432# smaller slot-sizes will be rejected. The header is smaller than
3433# 100 bytes.
3434#
3435#
3436# ==== COMMON OPTIONS ====
3437#
3438# no-store no new objects should be stored to this cache_dir.
3439#
3440# min-size=n the minimum object size in bytes this cache_dir
3441# will accept. It's used to restrict a cache_dir
3442# to only store large objects (e.g. AUFS) while
3443# other stores are optimized for smaller objects
3444# (e.g. Rock).
3445# Defaults to 0.
3446#
3447# max-size=n the maximum object size in bytes this cache_dir
3448# supports.
3449# The value in maximum_object_size directive sets
3450# the default unless more specific details are
3451# available (ie a small store capacity).
3452#
3453# Note: To make optimal use of the max-size limits you should order
3454# the cache_dir lines with the smallest max-size value first.
3455#
3456#Default:
3457# No disk cache. Store cache ojects only in memory.
3458#
3459
3460# Uncomment and adjust the following to add a disk cache directory.
3461#cache_dir ufs /var/spool/squid 100 16 256
3462
3463# TAG: store_dir_select_algorithm
3464# How Squid selects which cache_dir to use when the response
3465# object will fit into more than one.
3466#
3467# Regardless of which algorithm is used the cache_dir min-size
3468# and max-size parameters are obeyed. As such they can affect
3469# the selection algorithm by limiting the set of considered
3470# cache_dir.
3471#
3472# Algorithms:
3473#
3474# least-load
3475#
3476# This algorithm is suited to caches with similar cache_dir
3477# sizes and disk speeds.
3478#
3479# The disk with the least I/O pending is selected.
3480# When there are multiple disks with the same I/O load ranking
3481# the cache_dir with most available capacity is selected.
3482#
3483# When a mix of cache_dir sizes are configured the faster disks
3484# have a naturally lower I/O loading and larger disks have more
3485# capacity. So space used to store objects and data throughput
3486# may be very unbalanced towards larger disks.
3487#
3488#
3489# round-robin
3490#
3491# This algorithm is suited to caches with unequal cache_dir
3492# disk sizes.
3493#
3494# Each cache_dir is selected in a rotation. The next suitable
3495# cache_dir is used.
3496#
3497# Available cache_dir capacity is only considered in relation
3498# to whether the object will fit and meets the min-size and
3499# max-size parameters.
3500#
3501# Disk I/O loading is only considered to prevent overload on slow
3502# disks. This algorithm does not spread objects by size, so any
3503# I/O loading per-disk may appear very unbalanced and volatile.
3504#
3505# If several cache_dirs use similar min-size, max-size, or other
3506# limits to to reject certain responses, then do not group such
3507# cache_dir lines together, to avoid round-robin selection bias
3508# towards the first cache_dir after the group. Instead, interleave
3509# cache_dir lines from different groups. For example:
3510#
3511# store_dir_select_algorithm round-robin
3512# cache_dir rock /hdd1 ... min-size=100000
3513# cache_dir rock /ssd1 ... max-size=99999
3514# cache_dir rock /hdd2 ... min-size=100000
3515# cache_dir rock /ssd2 ... max-size=99999
3516# cache_dir rock /hdd3 ... min-size=100000
3517# cache_dir rock /ssd3 ... max-size=99999
3518#Default:
3519# store_dir_select_algorithm least-load
3520
3521# TAG: max_open_disk_fds
3522# To avoid having disk as the I/O bottleneck Squid can optionally
3523# bypass the on-disk cache if more than this amount of disk file
3524# descriptors are open.
3525#
3526# A value of 0 indicates no limit.
3527#Default:
3528# no limit
3529
3530# TAG: cache_swap_low (percent, 0-100)
3531# The low-water mark for AUFS/UFS/diskd cache object eviction by
3532# the cache_replacement_policy algorithm.
3533#
3534# Removal begins when the swap (disk) usage of a cache_dir is
3535# above this low-water mark and attempts to maintain utilization
3536# near the low-water mark.
3537#
3538# As swap utilization increases towards the high-water mark set
3539# by cache_swap_high object eviction becomes more agressive.
3540#
3541# The value difference in percentages between low- and high-water
3542# marks represent an eviction rate of 300 objects per second and
3543# the rate continues to scale in agressiveness by multiples of
3544# this above the high-water mark.
3545#
3546# Defaults are 90% and 95%. If you have a large cache, 5% could be
3547# hundreds of MB. If this is the case you may wish to set these
3548# numbers closer together.
3549#
3550# See also cache_swap_high and cache_replacement_policy
3551#Default:
3552# cache_swap_low 90
3553
3554# TAG: cache_swap_high (percent, 0-100)
3555# The high-water mark for AUFS/UFS/diskd cache object eviction by
3556# the cache_replacement_policy algorithm.
3557#
3558# Removal begins when the swap (disk) usage of a cache_dir is
3559# above the low-water mark set by cache_swap_low and attempts to
3560# maintain utilization near the low-water mark.
3561#
3562# As swap utilization increases towards this high-water mark object
3563# eviction becomes more agressive.
3564#
3565# The value difference in percentages between low- and high-water
3566# marks represent an eviction rate of 300 objects per second and
3567# the rate continues to scale in agressiveness by multiples of
3568# this above the high-water mark.
3569#
3570# Defaults are 90% and 95%. If you have a large cache, 5% could be
3571# hundreds of MB. If this is the case you may wish to set these
3572# numbers closer together.
3573#
3574# See also cache_swap_low and cache_replacement_policy
3575#Default:
3576# cache_swap_high 95
3577
3578# LOGFILE OPTIONS
3579# -----------------------------------------------------------------------------
3580
3581# TAG: logformat
3582# Usage:
3583#
3584# logformat <name> <format specification>
3585#
3586# Defines an access log format.
3587#
3588# The <format specification> is a string with embedded % format codes
3589#
3590# % format codes all follow the same basic structure where all but
3591# the formatcode is optional. Output strings are automatically escaped
3592# as required according to their context and the output format
3593# modifiers are usually not needed, but can be specified if an explicit
3594# output format is desired.
3595#
3596# % ["|[|'|#] [-] [[0]width] [{argument}] formatcode
3597#
3598# " output in quoted string format
3599# [ output in squid text log format as used by log_mime_hdrs
3600# # output in URL quoted format
3601# ' output as-is
3602#
3603# - left aligned
3604#
3605# width minimum and/or maximum field width:
3606# [width_min][.width_max]
3607# When minimum starts with 0, the field is zero-padded.
3608# String values exceeding maximum width are truncated.
3609#
3610# {arg} argument such as header name etc
3611#
3612# Format codes:
3613#
3614# % a literal % character
3615# sn Unique sequence number per log line entry
3616# err_code The ID of an error response served by Squid or
3617# a similar internal error identifier.
3618# err_detail Additional err_code-dependent error information.
3619# note The annotation specified by the argument. Also
3620# logs the adaptation meta headers set by the
3621# adaptation_meta configuration parameter.
3622# If no argument given all annotations logged.
3623# The argument may include a separator to use with
3624# annotation values:
3625# name[:separator]
3626# By default, multiple note values are separated with ","
3627# and multiple notes are separated with "\r\n".
3628# When logging named notes with %{name}note, the
3629# explicitly configured separator is used between note
3630# values. When logging all notes with %note, the
3631# explicitly configured separator is used between
3632# individual notes. There is currently no way to
3633# specify both value and notes separators when logging
3634# all notes with %note.
3635#
3636# Connection related format codes:
3637#
3638# >a Client source IP address
3639# >A Client FQDN
3640# >p Client source port
3641# >eui Client source EUI (MAC address, EUI-48 or EUI-64 identifier)
3642# >la Local IP address the client connected to
3643# >lp Local port number the client connected to
3644# >qos Client connection TOS/DSCP value set by Squid
3645# >nfmark Client connection netfilter mark set by Squid
3646#
3647# la Local listening IP address the client connection was connected to.
3648# lp Local listening port number the client connection was connected to.
3649#
3650# <a Server IP address of the last server or peer connection
3651# <A Server FQDN or peer name
3652# <p Server port number of the last server or peer connection
3653# <la Local IP address of the last server or peer connection
3654# <lp Local port number of the last server or peer connection
3655# <qos Server connection TOS/DSCP value set by Squid
3656# <nfmark Server connection netfilter mark set by Squid
3657#
3658# Time related format codes:
3659#
3660# ts Seconds since epoch
3661# tu subsecond time (milliseconds)
3662# tl Local time. Optional strftime format argument
3663# default %d/%b/%Y:%H:%M:%S %z
3664# tg GMT time. Optional strftime format argument
3665# default %d/%b/%Y:%H:%M:%S %z
3666# tr Response time (milliseconds)
3667# dt Total time spent making DNS lookups (milliseconds)
3668# tS Approximate master transaction start time in
3669# <full seconds since epoch>.<fractional seconds> format.
3670# Currently, Squid considers the master transaction
3671# started when a complete HTTP request header initiating
3672# the transaction is received from the client. This is
3673# the same value that Squid uses to calculate transaction
3674# response time when logging %tr to access.log. Currently,
3675# Squid uses millisecond resolution for %tS values,
3676# similar to the default access.log "current time" field
3677# (%ts.%03tu).
3678#
3679# Access Control related format codes:
3680#
3681# et Tag returned by external acl
3682# ea Log string returned by external acl
3683# un User name (any available)
3684# ul User name from authentication
3685# ue User name from external acl helper
3686# ui User name from ident
3687# un A user name. Expands to the first available name
3688# from the following list of information sources:
3689# - authenticated user name, like %ul
3690# - user name supplied by an external ACL, like %ue
3691# - SSL client name, like %us
3692# - ident user name, like %ui
3693# credentials Client credentials. The exact meaning depends on
3694# the authentication scheme: For Basic authentication,
3695# it is the password; for Digest, the realm sent by the
3696# client; for NTLM and Negotiate, the client challenge
3697# or client credentials prefixed with "YR " or "KK ".
3698#
3699# HTTP related format codes:
3700#
3701# REQUEST
3702#
3703# [http::]rm Request method (GET/POST etc)
3704# [http::]>rm Request method from client
3705# [http::]<rm Request method sent to server or peer
3706# [http::]ru Request URL from client (historic, filtered for logging)
3707# [http::]>ru Request URL from client
3708# [http::]<ru Request URL sent to server or peer
3709# [http::]>rs Request URL scheme from client
3710# [http::]<rs Request URL scheme sent to server or peer
3711# [http::]>rd Request URL domain from client
3712# [http::]<rd Request URL domain sent to server or peer
3713# [http::]>rP Request URL port from client
3714# [http::]<rP Request URL port sent to server or peer
3715# [http::]rp Request URL path excluding hostname
3716# [http::]>rp Request URL path excluding hostname from client
3717# [http::]<rp Request URL path excluding hostname sent to server or peer
3718# [http::]rv Request protocol version
3719# [http::]>rv Request protocol version from client
3720# [http::]<rv Request protocol version sent to server or peer
3721#
3722# [http::]>h Original received request header.
3723# Usually differs from the request header sent by
3724# Squid, although most fields are often preserved.
3725# Accepts optional header field name/value filter
3726# argument using name[:[separator]element] format.
3727# [http::]>ha Received request header after adaptation and
3728# redirection (pre-cache REQMOD vectoring point).
3729# Usually differs from the request header sent by
3730# Squid, although most fields are often preserved.
3731# Optional header name argument as for >h
3732#
3733#
3734# RESPONSE
3735#
3736# [http::]<Hs HTTP status code received from the next hop
3737# [http::]>Hs HTTP status code sent to the client
3738#
3739# [http::]<h Reply header. Optional header name argument
3740# as for >h
3741#
3742# [http::]mt MIME content type
3743#
3744#
3745# SIZE COUNTERS
3746#
3747# [http::]st Total size of request + reply traffic with client
3748# [http::]>st Total size of request received from client.
3749# Excluding chunked encoding bytes.
3750# [http::]<st Total size of reply sent to client (after adaptation)
3751#
3752# [http::]>sh Size of request headers received from client
3753# [http::]<sh Size of reply headers sent to client (after adaptation)
3754#
3755# [http::]<sH Reply high offset sent
3756# [http::]<sS Upstream object size
3757#
3758# [http::]<bs Number of HTTP-equivalent message body bytes
3759# received from the next hop, excluding chunked
3760# transfer encoding and control messages.
3761# Generated FTP/Gopher listings are treated as
3762# received bodies.
3763#
3764#
3765# TIMING
3766#
3767# [http::]<pt Peer response time in milliseconds. The timer starts
3768# when the last request byte is sent to the next hop
3769# and stops when the last response byte is received.
3770# [http::]<tt Total time in milliseconds. The timer
3771# starts with the first connect request (or write I/O)
3772# sent to the first selected peer. The timer stops
3773# with the last I/O with the last peer.
3774#
3775# Squid handling related format codes:
3776#
3777# Ss Squid request status (TCP_MISS etc)
3778# Sh Squid hierarchy status (DEFAULT_PARENT etc)
3779#
3780# SSL-related format codes:
3781#
3782# ssl::bump_mode SslBump decision for the transaction:
3783#
3784# For CONNECT requests that initiated bumping of
3785# a connection and for any request received on
3786# an already bumped connection, Squid logs the
3787# corresponding SslBump mode ("server-first" or
3788# "client-first"). See the ssl_bump option for
3789# more information about these modes.
3790#
3791# A "none" token is logged for requests that
3792# triggered "ssl_bump" ACL evaluation matching
3793# either a "none" rule or no rules at all.
3794#
3795# In all other cases, a single dash ("-") is
3796# logged.
3797#
3798# ssl::>sni SSL client SNI sent to Squid. Available only
3799# after the peek, stare, or splice SSL bumping
3800# actions.
3801#
3802# If ICAP is enabled, the following code becomes available (as
3803# well as ICAP log codes documented with the icap_log option):
3804#
3805# icap::tt Total ICAP processing time for the HTTP
3806# transaction. The timer ticks when ICAP
3807# ACLs are checked and when ICAP
3808# transaction is in progress.
3809#
3810# If adaptation is enabled the following three codes become available:
3811#
3812# adapt::<last_h The header of the last ICAP response or
3813# meta-information from the last eCAP
3814# transaction related to the HTTP transaction.
3815# Like <h, accepts an optional header name
3816# argument.
3817#
3818# adapt::sum_trs Summed adaptation transaction response
3819# times recorded as a comma-separated list in
3820# the order of transaction start time. Each time
3821# value is recorded as an integer number,
3822# representing response time of one or more
3823# adaptation (ICAP or eCAP) transaction in
3824# milliseconds. When a failed transaction is
3825# being retried or repeated, its time is not
3826# logged individually but added to the
3827# replacement (next) transaction. See also:
3828# adapt::all_trs.
3829#
3830# adapt::all_trs All adaptation transaction response times.
3831# Same as adaptation_strs but response times of
3832# individual transactions are never added
3833# together. Instead, all transaction response
3834# times are recorded individually.
3835#
3836# You can prefix adapt::*_trs format codes with adaptation
3837# service name in curly braces to record response time(s) specific
3838# to that service. For example: %{my_service}adapt::sum_trs
3839#
3840# If SSL is enabled, the following formating codes become available:
3841#
3842# %ssl::>cert_subject The Subject field of the received client
3843# SSL certificate or a dash ('-') if Squid has
3844# received an invalid/malformed certificate or
3845# no certificate at all. Consider encoding the
3846# logged value because Subject often has spaces.
3847#
3848# %ssl::>cert_issuer The Issuer field of the received client
3849# SSL certificate or a dash ('-') if Squid has
3850# received an invalid/malformed certificate or
3851# no certificate at all. Consider encoding the
3852# logged value because Issuer often has spaces.
3853#
3854# The default formats available (which do not need re-defining) are:
3855#
3856#logformat squid %ts.%03tu %6tr %>a %Ss/%03>Hs %<st %rm %ru %[un %Sh/%<a %mt
3857#logformat common %>a %[ui %[un [%tl] "%rm %ru HTTP/%rv" %>Hs %<st %Ss:%Sh
3858#logformat combined %>a %[ui %[un [%tl] "%rm %ru HTTP/%rv" %>Hs %<st "%{Referer}>h" "%{User-Agent}>h" %Ss:%Sh
3859#logformat referrer %ts.%03tu %>a %{Referer}>h %ru
3860#logformat useragent %>a [%tl] "%{User-Agent}>h"
3861#
3862# NOTE: When the log_mime_hdrs directive is set to ON.
3863# The squid, common and combined formats have a safely encoded copy
3864# of the mime headers appended to each line within a pair of brackets.
3865#
3866# NOTE: The common and combined formats are not quite true to the Apache definition.
3867# The logs from Squid contain an extra status and hierarchy code appended.
3868#
3869#Default:
3870# The format definitions squid, common, combined, referrer, useragent are built in.
3871
3872# TAG: access_log
3873# Configures whether and how Squid logs HTTP and ICP transactions.
3874# If access logging is enabled, a single line is logged for every
3875# matching HTTP or ICP request. The recommended directive formats are:
3876#
3877# access_log <module>:<place> [option ...] [acl acl ...]
3878# access_log none [acl acl ...]
3879#
3880# The following directive format is accepted but may be deprecated:
3881# access_log <module>:<place> [<logformat name> [acl acl ...]]
3882#
3883# In most cases, the first ACL name must not contain the '=' character
3884# and should not be equal to an existing logformat name. You can always
3885# start with an 'all' ACL to work around those restrictions.
3886#
3887# Will log to the specified module:place using the specified format (which
3888# must be defined in a logformat directive) those entries which match
3889# ALL the acl's specified (which must be defined in acl clauses).
3890# If no acl is specified, all requests will be logged to this destination.
3891#
3892# ===== Available options for the recommended directive format =====
3893#
3894# logformat=name Names log line format (either built-in or
3895# defined by a logformat directive). Defaults
3896# to 'squid'.
3897#
3898# buffer-size=64KB Defines approximate buffering limit for log
3899# records (see buffered_logs). Squid should not
3900# keep more than the specified size and, hence,
3901# should flush records before the buffer becomes
3902# full to avoid overflows under normal
3903# conditions (the exact flushing algorithm is
3904# module-dependent though). The on-error option
3905# controls overflow handling.
3906#
3907# on-error=die|drop Defines action on unrecoverable errors. The
3908# 'drop' action ignores (i.e., does not log)
3909# affected log records. The default 'die' action
3910# kills the affected worker. The drop action
3911# support has not been tested for modules other
3912# than tcp.
3913#
3914# ===== Modules Currently available =====
3915#
3916# none Do not log any requests matching these ACL.
3917# Do not specify Place or logformat name.
3918#
3919# stdio Write each log line to disk immediately at the completion of
3920# each request.
3921# Place: the filename and path to be written.
3922#
3923# daemon Very similar to stdio. But instead of writing to disk the log
3924# line is passed to a daemon helper for asychronous handling instead.
3925# Place: varies depending on the daemon.
3926#
3927# log_file_daemon Place: the file name and path to be written.
3928#
3929# syslog To log each request via syslog facility.
3930# Place: The syslog facility and priority level for these entries.
3931# Place Format: facility.priority
3932#
3933# where facility could be any of:
3934# authpriv, daemon, local0 ... local7 or user.
3935#
3936# And priority could be any of:
3937# err, warning, notice, info, debug.
3938#
3939# udp To send each log line as text data to a UDP receiver.
3940# Place: The destination host name or IP and port.
3941# Place Format: //host:port
3942#
3943# tcp To send each log line as text data to a TCP receiver.
3944# Lines may be accumulated before sending (see buffered_logs).
3945# Place: The destination host name or IP and port.
3946# Place Format: //host:port
3947#
3948# Default:
3949# access_log daemon:/var/log/squid/access.log squid
3950#Default:
3951# access_log daemon:/var/log/squid/access.log squid
3952
3953# TAG: icap_log
3954# ICAP log files record ICAP transaction summaries, one line per
3955# transaction.
3956#
3957# The icap_log option format is:
3958# icap_log <filepath> [<logformat name> [acl acl ...]]
3959# icap_log none [acl acl ...]]
3960#
3961# Please see access_log option documentation for details. The two
3962# kinds of logs share the overall configuration approach and many
3963# features.
3964#
3965# ICAP processing of a single HTTP message or transaction may
3966# require multiple ICAP transactions. In such cases, multiple
3967# ICAP transaction log lines will correspond to a single access
3968# log line.
3969#
3970# ICAP log supports many access.log logformat %codes. In ICAP context,
3971# HTTP message-related %codes are applied to the HTTP message embedded
3972# in an ICAP message. Logformat "%http::>..." codes are used for HTTP
3973# messages embedded in ICAP requests while "%http::<..." codes are used
3974# for HTTP messages embedded in ICAP responses. For example:
3975#
3976# http::>h To-be-adapted HTTP message headers sent by Squid to
3977# the ICAP service. For REQMOD transactions, these are
3978# HTTP request headers. For RESPMOD, these are HTTP
3979# response headers, but Squid currently cannot log them
3980# (i.e., %http::>h will expand to "-" for RESPMOD).
3981#
3982# http::<h Adapted HTTP message headers sent by the ICAP
3983# service to Squid (i.e., HTTP request headers in regular
3984# REQMOD; HTTP response headers in RESPMOD and during
3985# request satisfaction in REQMOD).
3986#
3987# ICAP OPTIONS transactions do not embed HTTP messages.
3988#
3989# Several logformat codes below deal with ICAP message bodies. An ICAP
3990# message body, if any, typically includes a complete HTTP message
3991# (required HTTP headers plus optional HTTP message body). When
3992# computing HTTP message body size for these logformat codes, Squid
3993# either includes or excludes chunked encoding overheads; see
3994# code-specific documentation for details.
3995#
3996# For Secure ICAP services, all size-related information is currently
3997# computed before/after TLS encryption/decryption, as if TLS was not
3998# in use at all.
3999#
4000# The following format codes are also available for ICAP logs:
4001#
4002# icap::<A ICAP server IP address. Similar to <A.
4003#
4004# icap::<service_name ICAP service name from the icap_service
4005# option in Squid configuration file.
4006#
4007# icap::ru ICAP Request-URI. Similar to ru.
4008#
4009# icap::rm ICAP request method (REQMOD, RESPMOD, or
4010# OPTIONS). Similar to existing rm.
4011#
4012# icap::>st The total size of the ICAP request sent to the ICAP
4013# server (ICAP headers + ICAP body), including chunking
4014# metadata (if any).
4015#
4016# icap::<st The total size of the ICAP response received from the
4017# ICAP server (ICAP headers + ICAP body), including
4018# chunking metadata (if any).
4019#
4020# icap::<bs The size of the ICAP response body received from the
4021# ICAP server, excluding chunking metadata (if any).
4022#
4023# icap::tr Transaction response time (in
4024# milliseconds). The timer starts when
4025# the ICAP transaction is created and
4026# stops when the transaction is completed.
4027# Similar to tr.
4028#
4029# icap::tio Transaction I/O time (in milliseconds). The
4030# timer starts when the first ICAP request
4031# byte is scheduled for sending. The timers
4032# stops when the last byte of the ICAP response
4033# is received.
4034#
4035# icap::to Transaction outcome: ICAP_ERR* for all
4036# transaction errors, ICAP_OPT for OPTION
4037# transactions, ICAP_ECHO for 204
4038# responses, ICAP_MOD for message
4039# modification, and ICAP_SAT for request
4040# satisfaction. Similar to Ss.
4041#
4042# icap::Hs ICAP response status code. Similar to Hs.
4043#
4044# icap::>h ICAP request header(s). Similar to >h.
4045#
4046# icap::<h ICAP response header(s). Similar to <h.
4047#
4048# The default ICAP log format, which can be used without an explicit
4049# definition, is called icap_squid:
4050#
4051#logformat icap_squid %ts.%03tu %6icap::tr %>A %icap::to/%03icap::Hs %icap::<st %icap::rm %icap::ru %un -/%icap::<A -
4052#
4053# See also: logformat and %adapt::<last_h
4054#Default:
4055# none
4056
4057# TAG: logfile_daemon
4058# Specify the path to the logfile-writing daemon. This daemon is
4059# used to write the access and store logs, if configured.
4060#
4061# Squid sends a number of commands to the log daemon:
4062# L<data>\n - logfile data
4063# R\n - rotate file
4064# T\n - truncate file
4065# O\n - reopen file
4066# F\n - flush file
4067# r<n>\n - set rotate count to <n>
4068# b<n>\n - 1 = buffer output, 0 = don't buffer output
4069#
4070# No responses is expected.
4071#Default:
4072# logfile_daemon /usr/lib/squid/log_file_daemon
4073
4074# TAG: stats_collection allow|deny acl acl...
4075# This options allows you to control which requests gets accounted
4076# in performance counters.
4077#
4078# This clause only supports fast acl types.
4079# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
4080#Default:
4081# Allow logging for all transactions.
4082
4083# TAG: cache_store_log
4084# Logs the activities of the storage manager. Shows which
4085# objects are ejected from the cache, and which objects are
4086# saved and for how long.
4087# There are not really utilities to analyze this data, so you can safely
4088# disable it (the default).
4089#
4090# Store log uses modular logging outputs. See access_log for the list
4091# of modules supported.
4092#
4093# Example:
4094# cache_store_log stdio:/var/log/squid/store.log
4095# cache_store_log daemon:/var/log/squid/store.log
4096#Default:
4097# none
4098
4099# TAG: cache_swap_state
4100# Location for the cache "swap.state" file. This index file holds
4101# the metadata of objects saved on disk. It is used to rebuild
4102# the cache during startup. Normally this file resides in each
4103# 'cache_dir' directory, but you may specify an alternate
4104# pathname here. Note you must give a full filename, not just
4105# a directory. Since this is the index for the whole object
4106# list you CANNOT periodically rotate it!
4107#
4108# If %s can be used in the file name it will be replaced with a
4109# a representation of the cache_dir name where each / is replaced
4110# with '.'. This is needed to allow adding/removing cache_dir
4111# lines when cache_swap_log is being used.
4112#
4113# If have more than one 'cache_dir', and %s is not used in the name
4114# these swap logs will have names such as:
4115#
4116# cache_swap_log.00
4117# cache_swap_log.01
4118# cache_swap_log.02
4119#
4120# The numbered extension (which is added automatically)
4121# corresponds to the order of the 'cache_dir' lines in this
4122# configuration file. If you change the order of the 'cache_dir'
4123# lines in this file, these index files will NOT correspond to
4124# the correct 'cache_dir' entry (unless you manually rename
4125# them). We recommend you do NOT use this option. It is
4126# better to keep these index files in each 'cache_dir' directory.
4127#Default:
4128# Store the journal inside its cache_dir
4129
4130# TAG: logfile_rotate
4131# Specifies the number of logfile rotations to make when you
4132# type 'squid -k rotate'. The default is 10, which will rotate
4133# with extensions 0 through 9. Setting logfile_rotate to 0 will
4134# disable the file name rotation, but the logfiles are still closed
4135# and re-opened. This will enable you to rename the logfiles
4136# yourself just before sending the rotate signal.
4137#
4138# Note, the 'squid -k rotate' command normally sends a USR1
4139# signal to the running squid process. In certain situations
4140# (e.g. on Linux with Async I/O), USR1 is used for other
4141# purposes, so -k rotate uses another signal. It is best to get
4142# in the habit of using 'squid -k rotate' instead of 'kill -USR1
4143# <pid>'.
4144#
4145# Note, from Squid-3.1 this option is only a default for cache.log,
4146# that log can be rotated separately by using debug_options.
4147#
4148# Note2, for Debian/Linux the default of logfile_rotate is
4149# zero, since it includes external logfile-rotation methods.
4150#Default:
4151# logfile_rotate 0
4152
4153# TAG: mime_table
4154# Path to Squid's icon configuration file.
4155#
4156# You shouldn't need to change this, but the default file contains
4157# examples and formatting information if you do.
4158#Default:
4159# mime_table /usr/share/squid/mime.conf
4160
4161# TAG: log_mime_hdrs on|off
4162# The Cache can record both the request and the response MIME
4163# headers for each HTTP transaction. The headers are encoded
4164# safely and will appear as two bracketed fields at the end of
4165# the access log (for either the native or httpd-emulated log
4166# formats). To enable this logging set log_mime_hdrs to 'on'.
4167#Default:
4168# log_mime_hdrs off
4169
4170# TAG: pid_filename
4171# A filename to write the process-id to. To disable, enter "none".
4172#Default:
4173# pid_filename /var/run/squid.pid
4174
4175# TAG: client_netmask
4176# A netmask for client addresses in logfiles and cachemgr output.
4177# Change this to protect the privacy of your cache clients.
4178# A netmask of 255.255.255.0 will log all IP's in that range with
4179# the last digit set to '0'.
4180#Default:
4181# Log full client IP address
4182
4183# TAG: strip_query_terms
4184# By default, Squid strips query terms from requested URLs before
4185# logging. This protects your user's privacy and reduces log size.
4186#
4187# When investigating HIT/MISS or other caching behaviour you
4188# will need to disable this to see the full URL used by Squid.
4189#Default:
4190# strip_query_terms on
4191
4192# TAG: buffered_logs on|off
4193# Whether to write/send access_log records ASAP or accumulate them and
4194# then write/send them in larger chunks. Buffering may improve
4195# performance because it decreases the number of I/Os. However,
4196# buffering increases the delay before log records become available to
4197# the final recipient (e.g., a disk file or logging daemon) and,
4198# hence, increases the risk of log records loss.
4199#
4200# Note that even when buffered_logs are off, Squid may have to buffer
4201# records if it cannot write/send them immediately due to pending I/Os
4202# (e.g., the I/O writing the previous log record) or connectivity loss.
4203#
4204# Currently honored by 'daemon' and 'tcp' access_log modules only.
4205#Default:
4206# buffered_logs off
4207
4208# TAG: netdb_filename
4209# Where Squid stores it's netdb journal.
4210# When enabled this journal preserves netdb state between restarts.
4211#
4212# To disable, enter "none".
4213#Default:
4214# netdb_filename stdio:/var/log/squid/netdb.state
4215
4216# OPTIONS FOR TROUBLESHOOTING
4217# -----------------------------------------------------------------------------
4218
4219# TAG: cache_log
4220# Squid administrative logging file.
4221#
4222# This is where general information about Squid behavior goes. You can
4223# increase the amount of data logged to this file and how often it is
4224# rotated with "debug_options"
4225#Default:
4226# cache_log /var/log/squid/cache.log
4227
4228# TAG: debug_options
4229# Logging options are set as section,level where each source file
4230# is assigned a unique section. Lower levels result in less
4231# output, Full debugging (level 9) can result in a very large
4232# log file, so be careful.
4233#
4234# The magic word "ALL" sets debugging levels for all sections.
4235# The default is to run with "ALL,1" to record important warnings.
4236#
4237# The rotate=N option can be used to keep more or less of these logs
4238# than would otherwise be kept by logfile_rotate.
4239# For most uses a single log should be enough to monitor current
4240# events affecting Squid.
4241#Default:
4242# Log all critical and important messages.
4243
4244# TAG: coredump_dir
4245# By default Squid leaves core files in the directory from where
4246# it was started. If you set 'coredump_dir' to a directory
4247# that exists, Squid will chdir() to that directory at startup
4248# and coredump files will be left there.
4249#
4250#Default:
4251# Use the directory from where Squid was started.
4252#
4253
4254# Leave coredumps in the first cache dir
4255coredump_dir /var/spool/squid
4256
4257# OPTIONS FOR FTP GATEWAYING
4258# -----------------------------------------------------------------------------
4259
4260# TAG: ftp_user
4261# If you want the anonymous login password to be more informative
4262# (and enable the use of picky FTP servers), set this to something
4263# reasonable for your domain, like wwwuser@somewhere.net
4264#
4265# The reason why this is domainless by default is the
4266# request can be made on the behalf of a user in any domain,
4267# depending on how the cache is used.
4268# Some FTP server also validate the email address is valid
4269# (for example perl.com).
4270#Default:
4271# ftp_user Squid@
4272
4273# TAG: ftp_passive
4274# If your firewall does not allow Squid to use passive
4275# connections, turn off this option.
4276#
4277# Use of ftp_epsv_all option requires this to be ON.
4278#Default:
4279# ftp_passive on
4280
4281# TAG: ftp_epsv_all
4282# FTP Protocol extensions permit the use of a special "EPSV ALL" command.
4283#
4284# NATs may be able to put the connection on a "fast path" through the
4285# translator, as the EPRT command will never be used and therefore,
4286# translation of the data portion of the segments will never be needed.
4287#
4288# When a client only expects to do two-way FTP transfers this may be
4289# useful.
4290# If squid finds that it must do a three-way FTP transfer after issuing
4291# an EPSV ALL command, the FTP session will fail.
4292#
4293# If you have any doubts about this option do not use it.
4294# Squid will nicely attempt all other connection methods.
4295#
4296# Requires ftp_passive to be ON (default) for any effect.
4297#Default:
4298# ftp_epsv_all off
4299
4300# TAG: ftp_epsv
4301# FTP Protocol extensions permit the use of a special "EPSV" command.
4302#
4303# NATs may be able to put the connection on a "fast path" through the
4304# translator using EPSV, as the EPRT command will never be used
4305# and therefore, translation of the data portion of the segments
4306# will never be needed.
4307#
4308# EPSV is often required to interoperate with FTP servers on IPv6
4309# networks. On the other hand, it may break some IPv4 servers.
4310#
4311# By default, EPSV may try EPSV with any FTP server. To fine tune
4312# that decision, you may restrict EPSV to certain clients or servers
4313# using ACLs:
4314#
4315# ftp_epsv allow|deny al1 acl2 ...
4316#
4317# WARNING: Disabling EPSV may cause problems with external NAT and IPv6.
4318#
4319# Only fast ACLs are supported.
4320# Requires ftp_passive to be ON (default) for any effect.
4321#Default:
4322# none
4323
4324# TAG: ftp_eprt
4325# FTP Protocol extensions permit the use of a special "EPRT" command.
4326#
4327# This extension provides a protocol neutral alternative to the
4328# IPv4-only PORT command. When supported it enables active FTP data
4329# channels over IPv6 and efficient NAT handling.
4330#
4331# Turning this OFF will prevent EPRT being attempted and will skip
4332# straight to using PORT for IPv4 servers.
4333#
4334# Some devices are known to not handle this extension correctly and
4335# may result in crashes. Devices which suport EPRT enough to fail
4336# cleanly will result in Squid attempting PORT anyway. This directive
4337# should only be disabled when EPRT results in device failures.
4338#
4339# WARNING: Doing so will convert Squid back to the old behavior with all
4340# the related problems with external NAT devices/layers and IPv4-only FTP.
4341#Default:
4342# ftp_eprt on
4343
4344# TAG: ftp_sanitycheck
4345# For security and data integrity reasons Squid by default performs
4346# sanity checks of the addresses of FTP data connections ensure the
4347# data connection is to the requested server. If you need to allow
4348# FTP connections to servers using another IP address for the data
4349# connection turn this off.
4350#Default:
4351# ftp_sanitycheck on
4352
4353# TAG: ftp_telnet_protocol
4354# The FTP protocol is officially defined to use the telnet protocol
4355# as transport channel for the control connection. However, many
4356# implementations are broken and does not respect this aspect of
4357# the FTP protocol.
4358#
4359# If you have trouble accessing files with ASCII code 255 in the
4360# path or similar problems involving this ASCII code you can
4361# try setting this directive to off. If that helps, report to the
4362# operator of the FTP server in question that their FTP server
4363# is broken and does not follow the FTP standard.
4364#Default:
4365# ftp_telnet_protocol on
4366
4367# OPTIONS FOR EXTERNAL SUPPORT PROGRAMS
4368# -----------------------------------------------------------------------------
4369
4370# TAG: diskd_program
4371# Specify the location of the diskd executable.
4372# Note this is only useful if you have compiled in
4373# diskd as one of the store io modules.
4374#Default:
4375# diskd_program /usr/lib/squid/diskd
4376
4377# TAG: unlinkd_program
4378# Specify the location of the executable for file deletion process.
4379#Default:
4380# unlinkd_program /usr/lib/squid/unlinkd
4381
4382# TAG: pinger_program
4383# Specify the location of the executable for the pinger process.
4384#Default:
4385# pinger_program /usr/lib/squid/pinger
4386
4387# TAG: pinger_enable
4388# Control whether the pinger is active at run-time.
4389# Enables turning ICMP pinger on and off with a simple
4390# squid -k reconfigure.
4391#Default:
4392# pinger_enable on
4393
4394# OPTIONS FOR URL REWRITING
4395# -----------------------------------------------------------------------------
4396
4397# TAG: url_rewrite_program
4398# Specify the location of the executable URL rewriter to use.
4399# Since they can perform almost any function there isn't one included.
4400#
4401# For each requested URL, the rewriter will receive on line with the format
4402#
4403# [channel-ID <SP>] URL [<SP> extras]<NL>
4404#
4405# See url_rewrite_extras on how to send "extras" with optional values to
4406# the helper.
4407# After processing the request the helper must reply using the following format:
4408#
4409# [channel-ID <SP>] result [<SP> kv-pairs]
4410#
4411# The result code can be:
4412#
4413# OK status=30N url="..."
4414# Redirect the URL to the one supplied in 'url='.
4415# 'status=' is optional and contains the status code to send
4416# the client in Squids HTTP response. It must be one of the
4417# HTTP redirect status codes: 301, 302, 303, 307, 308.
4418# When no status is given Squid will use 302.
4419#
4420# OK rewrite-url="..."
4421# Rewrite the URL to the one supplied in 'rewrite-url='.
4422# The new URL is fetched directly by Squid and returned to
4423# the client as the response to its request.
4424#
4425# OK
4426# When neither of url= and rewrite-url= are sent Squid does
4427# not change the URL.
4428#
4429# ERR
4430# Do not change the URL.
4431#
4432# BH
4433# An internal error occurred in the helper, preventing
4434# a result being identified. The 'message=' key name is
4435# reserved for delivering a log message.
4436#
4437#
4438# In addition to the above kv-pairs Squid also understands the following
4439# optional kv-pairs received from URL rewriters:
4440# clt_conn_tag=TAG
4441# Associates a TAG with the client TCP connection.
4442# The TAG is treated as a regular annotation but persists across
4443# future requests on the client connection rather than just the
4444# current request. A helper may update the TAG during subsequent
4445# requests be returning a new kv-pair.
4446#
4447# When using the concurrency= option the protocol is changed by
4448# introducing a query channel tag in front of the request/response.
4449# The query channel tag is a number between 0 and concurrency-1.
4450# This value must be echoed back unchanged to Squid as the first part
4451# of the response relating to its request.
4452#
4453# WARNING: URL re-writing ability should be avoided whenever possible.
4454# Use the URL redirect form of response instead.
4455#
4456# Re-write creates a difference in the state held by the client
4457# and server. Possibly causing confusion when the server response
4458# contains snippets of its view state. Embeded URLs, response
4459# and content Location headers, etc. are not re-written by this
4460# interface.
4461#
4462# By default, a URL rewriter is not used.
4463#Default:
4464# none
4465
4466# TAG: url_rewrite_children
4467# The maximum number of redirector processes to spawn. If you limit
4468# it too few Squid will have to wait for them to process a backlog of
4469# URLs, slowing it down. If you allow too many they will use RAM
4470# and other system resources noticably.
4471#
4472# The startup= and idle= options allow some measure of skew in your
4473# tuning.
4474#
4475# startup=
4476#
4477# Sets a minimum of how many processes are to be spawned when Squid
4478# starts or reconfigures. When set to zero the first request will
4479# cause spawning of the first child process to handle it.
4480#
4481# Starting too few will cause an initial slowdown in traffic as Squid
4482# attempts to simultaneously spawn enough processes to cope.
4483#
4484# idle=
4485#
4486# Sets a minimum of how many processes Squid is to try and keep available
4487# at all times. When traffic begins to rise above what the existing
4488# processes can handle this many more will be spawned up to the maximum
4489# configured. A minimum setting of 1 is required.
4490#
4491# concurrency=
4492#
4493# The number of requests each redirector helper can handle in
4494# parallel. Defaults to 0 which indicates the redirector
4495# is a old-style single threaded redirector.
4496#
4497# When this directive is set to a value >= 1 then the protocol
4498# used to communicate with the helper is modified to include
4499# an ID in front of the request/response. The ID from the request
4500# must be echoed back with the response to that request.
4501#Default:
4502# url_rewrite_children 20 startup=0 idle=1 concurrency=0
4503
4504# TAG: url_rewrite_host_header
4505# To preserve same-origin security policies in browsers and
4506# prevent Host: header forgery by redirectors Squid rewrites
4507# any Host: header in redirected requests.
4508#
4509# If you are running an accelerator this may not be a wanted
4510# effect of a redirector. This directive enables you disable
4511# Host: alteration in reverse-proxy traffic.
4512#
4513# WARNING: Entries are cached on the result of the URL rewriting
4514# process, so be careful if you have domain-virtual hosts.
4515#
4516# WARNING: Squid and other software verifies the URL and Host
4517# are matching, so be careful not to relay through other proxies
4518# or inspecting firewalls with this disabled.
4519#Default:
4520# url_rewrite_host_header on
4521
4522# TAG: url_rewrite_access
4523# If defined, this access list specifies which requests are
4524# sent to the redirector processes.
4525#
4526# This clause supports both fast and slow acl types.
4527# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
4528#Default:
4529# Allow, unless rules exist in squid.conf.
4530
4531# TAG: url_rewrite_bypass
4532# When this is 'on', a request will not go through the
4533# redirector if all the helpers are busy. If this is 'off'
4534# and the redirector queue grows too large, Squid will exit
4535# with a FATAL error and ask you to increase the number of
4536# redirectors. You should only enable this if the redirectors
4537# are not critical to your caching system. If you use
4538# redirectors for access control, and you enable this option,
4539# users may have access to pages they should not
4540# be allowed to request.
4541#Default:
4542# url_rewrite_bypass off
4543
4544# TAG: url_rewrite_extras
4545# Specifies a string to be append to request line format for the
4546# rewriter helper. "Quoted" format values may contain spaces and
4547# logformat %macros. In theory, any logformat %macro can be used.
4548# In practice, a %macro expands as a dash (-) if the helper request is
4549# sent before the required macro information is available to Squid.
4550#Default:
4551# url_rewrite_extras "%>a/%>A %un %>rm myip=%la myport=%lp"
4552
4553# OPTIONS FOR STORE ID
4554# -----------------------------------------------------------------------------
4555
4556# TAG: store_id_program
4557# Specify the location of the executable StoreID helper to use.
4558# Since they can perform almost any function there isn't one included.
4559#
4560# For each requested URL, the helper will receive one line with the format
4561#
4562# [channel-ID <SP>] URL [<SP> extras]<NL>
4563#
4564#
4565# After processing the request the helper must reply using the following format:
4566#
4567# [channel-ID <SP>] result [<SP> kv-pairs]
4568#
4569# The result code can be:
4570#
4571# OK store-id="..."
4572# Use the StoreID supplied in 'store-id='.
4573#
4574# ERR
4575# The default is to use HTTP request URL as the store ID.
4576#
4577# BH
4578# An internal error occured in the helper, preventing
4579# a result being identified.
4580#
4581# In addition to the above kv-pairs Squid also understands the following
4582# optional kv-pairs received from URL rewriters:
4583# clt_conn_tag=TAG
4584# Associates a TAG with the client TCP connection.
4585# Please see url_rewrite_program related documentation for this
4586# kv-pair
4587#
4588# Helper programs should be prepared to receive and possibly ignore
4589# additional whitespace-separated tokens on each input line.
4590#
4591# When using the concurrency= option the protocol is changed by
4592# introducing a query channel tag in front of the request/response.
4593# The query channel tag is a number between 0 and concurrency-1.
4594# This value must be echoed back unchanged to Squid as the first part
4595# of the response relating to its request.
4596#
4597# NOTE: when using StoreID refresh_pattern will apply to the StoreID
4598# returned from the helper and not the URL.
4599#
4600# WARNING: Wrong StoreID value returned by a careless helper may result
4601# in the wrong cached response returned to the user.
4602#
4603# By default, a StoreID helper is not used.
4604#Default:
4605# none
4606
4607# TAG: store_id_extras
4608# Specifies a string to be append to request line format for the
4609# StoreId helper. "Quoted" format values may contain spaces and
4610# logformat %macros. In theory, any logformat %macro can be used.
4611# In practice, a %macro expands as a dash (-) if the helper request is
4612# sent before the required macro information is available to Squid.
4613#Default:
4614# store_id_extras "%>a/%>A %un %>rm myip=%la myport=%lp"
4615
4616# TAG: store_id_children
4617# The maximum number of StoreID helper processes to spawn. If you limit
4618# it too few Squid will have to wait for them to process a backlog of
4619# requests, slowing it down. If you allow too many they will use RAM
4620# and other system resources noticably.
4621#
4622# The startup= and idle= options allow some measure of skew in your
4623# tuning.
4624#
4625# startup=
4626#
4627# Sets a minimum of how many processes are to be spawned when Squid
4628# starts or reconfigures. When set to zero the first request will
4629# cause spawning of the first child process to handle it.
4630#
4631# Starting too few will cause an initial slowdown in traffic as Squid
4632# attempts to simultaneously spawn enough processes to cope.
4633#
4634# idle=
4635#
4636# Sets a minimum of how many processes Squid is to try and keep available
4637# at all times. When traffic begins to rise above what the existing
4638# processes can handle this many more will be spawned up to the maximum
4639# configured. A minimum setting of 1 is required.
4640#
4641# concurrency=
4642#
4643# The number of requests each storeID helper can handle in
4644# parallel. Defaults to 0 which indicates the helper
4645# is a old-style single threaded program.
4646#
4647# When this directive is set to a value >= 1 then the protocol
4648# used to communicate with the helper is modified to include
4649# an ID in front of the request/response. The ID from the request
4650# must be echoed back with the response to that request.
4651#Default:
4652# store_id_children 20 startup=0 idle=1 concurrency=0
4653
4654# TAG: store_id_access
4655# If defined, this access list specifies which requests are
4656# sent to the StoreID processes. By default all requests
4657# are sent.
4658#
4659# This clause supports both fast and slow acl types.
4660# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
4661#Default:
4662# Allow, unless rules exist in squid.conf.
4663
4664# TAG: store_id_bypass
4665# When this is 'on', a request will not go through the
4666# helper if all helpers are busy. If this is 'off'
4667# and the helper queue grows too large, Squid will exit
4668# with a FATAL error and ask you to increase the number of
4669# helpers. You should only enable this if the helperss
4670# are not critical to your caching system. If you use
4671# helpers for critical caching components, and you enable this
4672# option, users may not get objects from cache.
4673#Default:
4674# store_id_bypass on
4675
4676# OPTIONS FOR TUNING THE CACHE
4677# -----------------------------------------------------------------------------
4678
4679# TAG: cache
4680# Requests denied by this directive will not be served from the cache
4681# and their responses will not be stored in the cache. This directive
4682# has no effect on other transactions and on already cached responses.
4683#
4684# This clause supports both fast and slow acl types.
4685# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
4686#
4687# This and the two other similar caching directives listed below are
4688# checked at different transaction processing stages, have different
4689# access to response information, affect different cache operations,
4690# and differ in slow ACLs support:
4691#
4692# * cache: Checked before Squid makes a hit/miss determination.
4693# No access to reply information!
4694# Denies both serving a hit and storing a miss.
4695# Supports both fast and slow ACLs.
4696# * send_hit: Checked after a hit was detected.
4697# Has access to reply (hit) information.
4698# Denies serving a hit only.
4699# Supports fast ACLs only.
4700# * store_miss: Checked before storing a cachable miss.
4701# Has access to reply (miss) information.
4702# Denies storing a miss only.
4703# Supports fast ACLs only.
4704#
4705# If you are not sure which of the three directives to use, apply the
4706# following decision logic:
4707#
4708# * If your ACL(s) are of slow type _and_ need response info, redesign.
4709# Squid does not support that particular combination at this time.
4710# Otherwise:
4711# * If your directive ACL(s) are of slow type, use "cache"; and/or
4712# * if your directive ACL(s) need no response info, use "cache".
4713# Otherwise:
4714# * If you do not want the response cached, use store_miss; and/or
4715# * if you do not want a hit on a cached response, use send_hit.
4716#Default:
4717# By default, this directive is unused and has no effect.
4718
4719# TAG: send_hit
4720# Responses denied by this directive will not be served from the cache
4721# (but may still be cached, see store_miss). This directive has no
4722# effect on the responses it allows and on the cached objects.
4723#
4724# Please see the "cache" directive for a summary of differences among
4725# store_miss, send_hit, and cache directives.
4726#
4727# Unlike the "cache" directive, send_hit only supports fast acl
4728# types. See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
4729#
4730# For example:
4731#
4732# # apply custom Store ID mapping to some URLs
4733# acl MapMe dstdomain .c.example.com
4734# store_id_program ...
4735# store_id_access allow MapMe
4736#
4737# # but prevent caching of special responses
4738# # such as 302 redirects that cause StoreID loops
4739# acl Ordinary http_status 200-299
4740# store_miss deny MapMe !Ordinary
4741#
4742# # and do not serve any previously stored special responses
4743# # from the cache (in case they were already cached before
4744# # the above store_miss rule was in effect).
4745# send_hit deny MapMe !Ordinary
4746#Default:
4747# By default, this directive is unused and has no effect.
4748
4749# TAG: store_miss
4750# Responses denied by this directive will not be cached (but may still
4751# be served from the cache, see send_hit). This directive has no
4752# effect on the responses it allows and on the already cached responses.
4753#
4754# Please see the "cache" directive for a summary of differences among
4755# store_miss, send_hit, and cache directives. See the
4756# send_hit directive for a usage example.
4757#
4758# Unlike the "cache" directive, store_miss only supports fast acl
4759# types. See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
4760#Default:
4761# By default, this directive is unused and has no effect.
4762
4763# TAG: max_stale time-units
4764# This option puts an upper limit on how stale content Squid
4765# will serve from the cache if cache validation fails.
4766# Can be overriden by the refresh_pattern max-stale option.
4767#Default:
4768# max_stale 1 week
4769
4770# TAG: refresh_pattern
4771# usage: refresh_pattern [-i] regex min percent max [options]
4772#
4773# By default, regular expressions are CASE-SENSITIVE. To make
4774# them case-insensitive, use the -i option.
4775#
4776# 'Min' is the time (in minutes) an object without an explicit
4777# expiry time should be considered fresh. The recommended
4778# value is 0, any higher values may cause dynamic applications
4779# to be erroneously cached unless the application designer
4780# has taken the appropriate actions.
4781#
4782# 'Percent' is a percentage of the objects age (time since last
4783# modification age) an object without explicit expiry time
4784# will be considered fresh.
4785#
4786# 'Max' is an upper limit on how long objects without an explicit
4787# expiry time will be considered fresh. The value is also used
4788# to form Cache-Control: max-age header for a request sent from
4789# Squid to origin/parent.
4790#
4791# options: override-expire
4792# override-lastmod
4793# reload-into-ims
4794# ignore-reload
4795# ignore-no-store
4796# ignore-must-revalidate
4797# ignore-private
4798# ignore-auth
4799# max-stale=NN
4800# refresh-ims
4801# store-stale
4802#
4803# override-expire enforces min age even if the server
4804# sent an explicit expiry time (e.g., with the
4805# Expires: header or Cache-Control: max-age). Doing this
4806# VIOLATES the HTTP standard. Enabling this feature
4807# could make you liable for problems which it causes.
4808#
4809# Note: override-expire does not enforce staleness - it only extends
4810# freshness / min. If the server returns a Expires time which
4811# is longer than your max time, Squid will still consider
4812# the object fresh for that period of time.
4813#
4814# override-lastmod enforces min age even on objects
4815# that were modified recently.
4816#
4817# reload-into-ims changes a client no-cache or ``reload''
4818# request for a cached entry into a conditional request using
4819# If-Modified-Since and/or If-None-Match headers, provided the
4820# cached entry has a Last-Modified and/or a strong ETag header.
4821# Doing this VIOLATES the HTTP standard. Enabling this feature
4822# could make you liable for problems which it causes.
4823#
4824# ignore-reload ignores a client no-cache or ``reload''
4825# header. Doing this VIOLATES the HTTP standard. Enabling
4826# this feature could make you liable for problems which
4827# it causes.
4828#
4829# ignore-no-store ignores any ``Cache-control: no-store''
4830# headers received from a server. Doing this VIOLATES
4831# the HTTP standard. Enabling this feature could make you
4832# liable for problems which it causes.
4833#
4834# ignore-must-revalidate ignores any ``Cache-Control: must-revalidate``
4835# headers received from a server. Doing this VIOLATES
4836# the HTTP standard. Enabling this feature could make you
4837# liable for problems which it causes.
4838#
4839# ignore-private ignores any ``Cache-control: private''
4840# headers received from a server. Doing this VIOLATES
4841# the HTTP standard. Enabling this feature could make you
4842# liable for problems which it causes.
4843#
4844# ignore-auth caches responses to requests with authorization,
4845# as if the originserver had sent ``Cache-control: public''
4846# in the response header. Doing this VIOLATES the HTTP standard.
4847# Enabling this feature could make you liable for problems which
4848# it causes.
4849#
4850# refresh-ims causes squid to contact the origin server
4851# when a client issues an If-Modified-Since request. This
4852# ensures that the client will receive an updated version
4853# if one is available.
4854#
4855# store-stale stores responses even if they don't have explicit
4856# freshness or a validator (i.e., Last-Modified or an ETag)
4857# present, or if they're already stale. By default, Squid will
4858# not cache such responses because they usually can't be
4859# reused. Note that such responses will be stale by default.
4860#
4861# max-stale=NN provide a maximum staleness factor. Squid won't
4862# serve objects more stale than this even if it failed to
4863# validate the object. Default: use the max_stale global limit.
4864#
4865# Basically a cached object is:
4866#
4867# FRESH if expire > now, else STALE
4868# STALE if age > max
4869# FRESH if lm-factor < percent, else STALE
4870# FRESH if age < min
4871# else STALE
4872#
4873# The refresh_pattern lines are checked in the order listed here.
4874# The first entry which matches is used. If none of the entries
4875# match the default will be used.
4876#
4877# Note, you must uncomment all the default lines if you want
4878# to change one. The default setting is only active if none is
4879# used.
4880#
4881#
4882
4883#
4884# Add any of your own refresh_pattern entries above these.
4885#
4886refresh_pattern ^ftp: 1440 20% 10080
4887refresh_pattern ^gopher: 1440 0% 1440
4888refresh_pattern -i (/cgi-bin/|\?) 0 0% 0
4889refresh_pattern (Release|Packages(.gz)*)$ 0 20% 2880
4890# example lin deb packages
4891#refresh_pattern (\.deb|\.udeb)$ 129600 100% 129600
4892refresh_pattern . 0 20% 4320
4893
4894# TAG: quick_abort_min (KB)
4895#Default:
4896# quick_abort_min 16 KB
4897
4898# TAG: quick_abort_max (KB)
4899#Default:
4900# quick_abort_max 16 KB
4901
4902# TAG: quick_abort_pct (percent)
4903# The cache by default continues downloading aborted requests
4904# which are almost completed (less than 16 KB remaining). This
4905# may be undesirable on slow (e.g. SLIP) links and/or very busy
4906# caches. Impatient users may tie up file descriptors and
4907# bandwidth by repeatedly requesting and immediately aborting
4908# downloads.
4909#
4910# When the user aborts a request, Squid will check the
4911# quick_abort values to the amount of data transferred until
4912# then.
4913#
4914# If the transfer has less than 'quick_abort_min' KB remaining,
4915# it will finish the retrieval.
4916#
4917# If the transfer has more than 'quick_abort_max' KB remaining,
4918# it will abort the retrieval.
4919#
4920# If more than 'quick_abort_pct' of the transfer has completed,
4921# it will finish the retrieval.
4922#
4923# If you do not want any retrieval to continue after the client
4924# has aborted, set both 'quick_abort_min' and 'quick_abort_max'
4925# to '0 KB'.
4926#
4927# If you want retrievals to always continue if they are being
4928# cached set 'quick_abort_min' to '-1 KB'.
4929#Default:
4930# quick_abort_pct 95
4931
4932# TAG: read_ahead_gap buffer-size
4933# The amount of data the cache will buffer ahead of what has been
4934# sent to the client when retrieving an object from another server.
4935#Default:
4936# read_ahead_gap 16 KB
4937
4938# TAG: negative_ttl time-units
4939# Set the Default Time-to-Live (TTL) for failed requests.
4940# Certain types of failures (such as "connection refused" and
4941# "404 Not Found") are able to be negatively-cached for a short time.
4942# Modern web servers should provide Expires: header, however if they
4943# do not this can provide a minimum TTL.
4944# The default is not to cache errors with unknown expiry details.
4945#
4946# Note that this is different from negative caching of DNS lookups.
4947#
4948# WARNING: Doing this VIOLATES the HTTP standard. Enabling
4949# this feature could make you liable for problems which it
4950# causes.
4951#Default:
4952# negative_ttl 0 seconds
4953
4954# TAG: positive_dns_ttl time-units
4955# Upper limit on how long Squid will cache positive DNS responses.
4956# Default is 6 hours (360 minutes). This directive must be set
4957# larger than negative_dns_ttl.
4958#Default:
4959# positive_dns_ttl 6 hours
4960
4961# TAG: negative_dns_ttl time-units
4962# Time-to-Live (TTL) for negative caching of failed DNS lookups.
4963# This also sets the lower cache limit on positive lookups.
4964# Minimum value is 1 second, and it is not recommendable to go
4965# much below 10 seconds.
4966#Default:
4967# negative_dns_ttl 1 minutes
4968
4969# TAG: range_offset_limit size [acl acl...]
4970# usage: (size) [units] [[!]aclname]
4971#
4972# Sets an upper limit on how far (number of bytes) into the file
4973# a Range request may be to cause Squid to prefetch the whole file.
4974# If beyond this limit, Squid forwards the Range request as it is and
4975# the result is NOT cached.
4976#
4977# This is to stop a far ahead range request (lets say start at 17MB)
4978# from making Squid fetch the whole object up to that point before
4979# sending anything to the client.
4980#
4981# Multiple range_offset_limit lines may be specified, and they will
4982# be searched from top to bottom on each request until a match is found.
4983# The first match found will be used. If no line matches a request, the
4984# default limit of 0 bytes will be used.
4985#
4986# 'size' is the limit specified as a number of units.
4987#
4988# 'units' specifies whether to use bytes, KB, MB, etc.
4989# If no units are specified bytes are assumed.
4990#
4991# A size of 0 causes Squid to never fetch more than the
4992# client requested. (default)
4993#
4994# A size of 'none' causes Squid to always fetch the object from the
4995# beginning so it may cache the result. (2.0 style)
4996#
4997# 'aclname' is the name of a defined ACL.
4998#
4999# NP: Using 'none' as the byte value here will override any quick_abort settings
5000# that may otherwise apply to the range request. The range request will
5001# be fully fetched from start to finish regardless of the client
5002# actions. This affects bandwidth usage.
5003#Default:
5004# none
5005
5006# TAG: minimum_expiry_time (seconds)
5007# The minimum caching time according to (Expires - Date)
5008# headers Squid honors if the object can't be revalidated.
5009# The default is 60 seconds.
5010#
5011# In reverse proxy environments it might be desirable to honor
5012# shorter object lifetimes. It is most likely better to make
5013# your server return a meaningful Last-Modified header however.
5014#
5015# In ESI environments where page fragments often have short
5016# lifetimes, this will often be best set to 0.
5017#Default:
5018# minimum_expiry_time 60 seconds
5019
5020# TAG: store_avg_object_size (bytes)
5021# Average object size, used to estimate number of objects your
5022# cache can hold. The default is 13 KB.
5023#
5024# This is used to pre-seed the cache index memory allocation to
5025# reduce expensive reallocate operations while handling clients
5026# traffic. Too-large values may result in memory allocation during
5027# peak traffic, too-small values will result in wasted memory.
5028#
5029# Check the cache manager 'info' report metrics for the real
5030# object sizes seen by your Squid before tuning this.
5031#Default:
5032# store_avg_object_size 13 KB
5033
5034# TAG: store_objects_per_bucket
5035# Target number of objects per bucket in the store hash table.
5036# Lowering this value increases the total number of buckets and
5037# also the storage maintenance rate. The default is 20.
5038#Default:
5039# store_objects_per_bucket 20
5040
5041# HTTP OPTIONS
5042# -----------------------------------------------------------------------------
5043
5044# TAG: request_header_max_size (KB)
5045# This specifies the maximum size for HTTP headers in a request.
5046# Request headers are usually relatively small (about 512 bytes).
5047# Placing a limit on the request header size will catch certain
5048# bugs (for example with persistent connections) and possibly
5049# buffer-overflow or denial-of-service attacks.
5050#Default:
5051# request_header_max_size 64 KB
5052
5053# TAG: reply_header_max_size (KB)
5054# This specifies the maximum size for HTTP headers in a reply.
5055# Reply headers are usually relatively small (about 512 bytes).
5056# Placing a limit on the reply header size will catch certain
5057# bugs (for example with persistent connections) and possibly
5058# buffer-overflow or denial-of-service attacks.
5059#Default:
5060# reply_header_max_size 64 KB
5061
5062# TAG: request_body_max_size (bytes)
5063# This specifies the maximum size for an HTTP request body.
5064# In other words, the maximum size of a PUT/POST request.
5065# A user who attempts to send a request with a body larger
5066# than this limit receives an "Invalid Request" error message.
5067# If you set this parameter to a zero (the default), there will
5068# be no limit imposed.
5069#
5070# See also client_request_buffer_max_size for an alternative
5071# limitation on client uploads which can be configured.
5072#Default:
5073# No limit.
5074
5075# TAG: client_request_buffer_max_size (bytes)
5076# This specifies the maximum buffer size of a client request.
5077# It prevents squid eating too much memory when somebody uploads
5078# a large file.
5079#Default:
5080# client_request_buffer_max_size 512 KB
5081
5082# TAG: broken_posts
5083# A list of ACL elements which, if matched, causes Squid to send
5084# an extra CRLF pair after the body of a PUT/POST request.
5085#
5086# Some HTTP servers has broken implementations of PUT/POST,
5087# and rely on an extra CRLF pair sent by some WWW clients.
5088#
5089# Quote from RFC2616 section 4.1 on this matter:
5090#
5091# Note: certain buggy HTTP/1.0 client implementations generate an
5092# extra CRLF's after a POST request. To restate what is explicitly
5093# forbidden by the BNF, an HTTP/1.1 client must not preface or follow
5094# a request with an extra CRLF.
5095#
5096# This clause only supports fast acl types.
5097# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
5098#
5099#Example:
5100# acl buggy_server url_regex ^http://....
5101# broken_posts allow buggy_server
5102#Default:
5103# Obey RFC 2616.
5104
5105# TAG: adaptation_uses_indirect_client on|off
5106# Controls whether the indirect client IP address (instead of the direct
5107# client IP address) is passed to adaptation services.
5108#
5109# See also: follow_x_forwarded_for adaptation_send_client_ip
5110#Default:
5111# adaptation_uses_indirect_client on
5112
5113# TAG: via on|off
5114# If set (default), Squid will include a Via header in requests and
5115# replies as required by RFC2616.
5116#Default:
5117# via on
5118
5119# TAG: ie_refresh on|off
5120# Microsoft Internet Explorer up until version 5.5 Service
5121# Pack 1 has an issue with transparent proxies, wherein it
5122# is impossible to force a refresh. Turning this on provides
5123# a partial fix to the problem, by causing all IMS-REFRESH
5124# requests from older IE versions to check the origin server
5125# for fresh content. This reduces hit ratio by some amount
5126# (~10% in my experience), but allows users to actually get
5127# fresh content when they want it. Note because Squid
5128# cannot tell if the user is using 5.5 or 5.5SP1, the behavior
5129# of 5.5 is unchanged from old versions of Squid (i.e. a
5130# forced refresh is impossible). Newer versions of IE will,
5131# hopefully, continue to have the new behavior and will be
5132# handled based on that assumption. This option defaults to
5133# the old Squid behavior, which is better for hit ratios but
5134# worse for clients using IE, if they need to be able to
5135# force fresh content.
5136#Default:
5137# ie_refresh off
5138
5139# TAG: vary_ignore_expire on|off
5140# Many HTTP servers supporting Vary gives such objects
5141# immediate expiry time with no cache-control header
5142# when requested by a HTTP/1.0 client. This option
5143# enables Squid to ignore such expiry times until
5144# HTTP/1.1 is fully implemented.
5145#
5146# WARNING: If turned on this may eventually cause some
5147# varying objects not intended for caching to get cached.
5148#Default:
5149# vary_ignore_expire off
5150
5151# TAG: request_entities
5152# Squid defaults to deny GET and HEAD requests with request entities,
5153# as the meaning of such requests are undefined in the HTTP standard
5154# even if not explicitly forbidden.
5155#
5156# Set this directive to on if you have clients which insists
5157# on sending request entities in GET or HEAD requests. But be warned
5158# that there is server software (both proxies and web servers) which
5159# can fail to properly process this kind of request which may make you
5160# vulnerable to cache pollution attacks if enabled.
5161#Default:
5162# request_entities off
5163
5164# TAG: request_header_access
5165# Usage: request_header_access header_name allow|deny [!]aclname ...
5166#
5167# WARNING: Doing this VIOLATES the HTTP standard. Enabling
5168# this feature could make you liable for problems which it
5169# causes.
5170#
5171# This option replaces the old 'anonymize_headers' and the
5172# older 'http_anonymizer' option with something that is much
5173# more configurable. A list of ACLs for each header name allows
5174# removal of specific header fields under specific conditions.
5175#
5176# This option only applies to outgoing HTTP request headers (i.e.,
5177# headers sent by Squid to the next HTTP hop such as a cache peer
5178# or an origin server). The option has no effect during cache hit
5179# detection. The equivalent adaptation vectoring point in ICAP
5180# terminology is post-cache REQMOD.
5181#
5182# The option is applied to individual outgoing request header
5183# fields. For each request header field F, Squid uses the first
5184# qualifying sets of request_header_access rules:
5185#
5186# 1. Rules with header_name equal to F's name.
5187# 2. Rules with header_name 'Other', provided F's name is not
5188# on the hard-coded list of commonly used HTTP header names.
5189# 3. Rules with header_name 'All'.
5190#
5191# Within that qualifying rule set, rule ACLs are checked as usual.
5192# If ACLs of an "allow" rule match, the header field is allowed to
5193# go through as is. If ACLs of a "deny" rule match, the header is
5194# removed and request_header_replace is then checked to identify
5195# if the removed header has a replacement. If no rules within the
5196# set have matching ACLs, the header field is left as is.
5197#
5198# For example, to achieve the same behavior as the old
5199# 'http_anonymizer standard' option, you should use:
5200#
5201# request_header_access From deny all
5202# request_header_access Referer deny all
5203# request_header_access User-Agent deny all
5204#
5205# Or, to reproduce the old 'http_anonymizer paranoid' feature
5206# you should use:
5207#
5208# request_header_access Authorization allow all
5209# request_header_access Proxy-Authorization allow all
5210# request_header_access Cache-Control allow all
5211# request_header_access Content-Length allow all
5212# request_header_access Content-Type allow all
5213# request_header_access Date allow all
5214# request_header_access Host allow all
5215# request_header_access If-Modified-Since allow all
5216# request_header_access Pragma allow all
5217# request_header_access Accept allow all
5218# request_header_access Accept-Charset allow all
5219# request_header_access Accept-Encoding allow all
5220# request_header_access Accept-Language allow all
5221# request_header_access Connection allow all
5222# request_header_access All deny all
5223#
5224# HTTP reply headers are controlled with the reply_header_access directive.
5225#
5226# By default, all headers are allowed (no anonymizing is performed).
5227#Default:
5228# No limits.
5229
5230# TAG: reply_header_access
5231# Usage: reply_header_access header_name allow|deny [!]aclname ...
5232#
5233# WARNING: Doing this VIOLATES the HTTP standard. Enabling
5234# this feature could make you liable for problems which it
5235# causes.
5236#
5237# This option only applies to reply headers, i.e., from the
5238# server to the client.
5239#
5240# This is the same as request_header_access, but in the other
5241# direction. Please see request_header_access for detailed
5242# documentation.
5243#
5244# For example, to achieve the same behavior as the old
5245# 'http_anonymizer standard' option, you should use:
5246#
5247# reply_header_access Server deny all
5248# reply_header_access WWW-Authenticate deny all
5249# reply_header_access Link deny all
5250#
5251# Or, to reproduce the old 'http_anonymizer paranoid' feature
5252# you should use:
5253#
5254# reply_header_access Allow allow all
5255# reply_header_access WWW-Authenticate allow all
5256# reply_header_access Proxy-Authenticate allow all
5257# reply_header_access Cache-Control allow all
5258# reply_header_access Content-Encoding allow all
5259# reply_header_access Content-Length allow all
5260# reply_header_access Content-Type allow all
5261# reply_header_access Date allow all
5262# reply_header_access Expires allow all
5263# reply_header_access Last-Modified allow all
5264# reply_header_access Location allow all
5265# reply_header_access Pragma allow all
5266# reply_header_access Content-Language allow all
5267# reply_header_access Retry-After allow all
5268# reply_header_access Title allow all
5269# reply_header_access Content-Disposition allow all
5270# reply_header_access Connection allow all
5271# reply_header_access All deny all
5272#
5273# HTTP request headers are controlled with the request_header_access directive.
5274#
5275# By default, all headers are allowed (no anonymizing is
5276# performed).
5277#Default:
5278# No limits.
5279
5280# TAG: request_header_replace
5281# Usage: request_header_replace header_name message
5282# Example: request_header_replace User-Agent Nutscrape/1.0 (CP/M; 8-bit)
5283#
5284# This option allows you to change the contents of headers
5285# denied with request_header_access above, by replacing them
5286# with some fixed string.
5287#
5288# This only applies to request headers, not reply headers.
5289#
5290# By default, headers are removed if denied.
5291#Default:
5292# none
5293
5294# TAG: reply_header_replace
5295# Usage: reply_header_replace header_name message
5296# Example: reply_header_replace Server Foo/1.0
5297#
5298# This option allows you to change the contents of headers
5299# denied with reply_header_access above, by replacing them
5300# with some fixed string.
5301#
5302# This only applies to reply headers, not request headers.
5303#
5304# By default, headers are removed if denied.
5305#Default:
5306# none
5307
5308# TAG: request_header_add
5309# Usage: request_header_add field-name field-value acl1 [acl2] ...
5310# Example: request_header_add X-Client-CA "CA=%ssl::>cert_issuer" all
5311#
5312# This option adds header fields to outgoing HTTP requests (i.e.,
5313# request headers sent by Squid to the next HTTP hop such as a
5314# cache peer or an origin server). The option has no effect during
5315# cache hit detection. The equivalent adaptation vectoring point
5316# in ICAP terminology is post-cache REQMOD.
5317#
5318# Field-name is a token specifying an HTTP header name. If a
5319# standard HTTP header name is used, Squid does not check whether
5320# the new header conflicts with any existing headers or violates
5321# HTTP rules. If the request to be modified already contains a
5322# field with the same name, the old field is preserved but the
5323# header field values are not merged.
5324#
5325# Field-value is either a token or a quoted string. If quoted
5326# string format is used, then the surrounding quotes are removed
5327# while escape sequences and %macros are processed.
5328#
5329# In theory, all of the logformat codes can be used as %macros.
5330# However, unlike logging (which happens at the very end of
5331# transaction lifetime), the transaction may not yet have enough
5332# information to expand a macro when the new header value is needed.
5333# And some information may already be available to Squid but not yet
5334# committed where the macro expansion code can access it (report
5335# such instances!). The macro will be expanded into a single dash
5336# ('-') in such cases. Not all macros have been tested.
5337#
5338# One or more Squid ACLs may be specified to restrict header
5339# injection to matching requests. As always in squid.conf, all
5340# ACLs in an option ACL list must be satisfied for the insertion
5341# to happen. The request_header_add option supports fast ACLs
5342# only.
5343#Default:
5344# none
5345
5346# TAG: note
5347# This option used to log custom information about the master
5348# transaction. For example, an admin may configure Squid to log
5349# which "user group" the transaction belongs to, where "user group"
5350# will be determined based on a set of ACLs and not [just]
5351# authentication information.
5352# Values of key/value pairs can be logged using %{key}note macros:
5353#
5354# note key value acl ...
5355# logformat myFormat ... %{key}note ...
5356#Default:
5357# none
5358
5359# TAG: relaxed_header_parser on|off|warn
5360# In the default "on" setting Squid accepts certain forms
5361# of non-compliant HTTP messages where it is unambiguous
5362# what the sending application intended even if the message
5363# is not correctly formatted. The messages is then normalized
5364# to the correct form when forwarded by Squid.
5365#
5366# If set to "warn" then a warning will be emitted in cache.log
5367# each time such HTTP error is encountered.
5368#
5369# If set to "off" then such HTTP errors will cause the request
5370# or response to be rejected.
5371#Default:
5372# relaxed_header_parser on
5373
5374# TAG: collapsed_forwarding (on|off)
5375# When enabled, instead of forwarding each concurrent request for
5376# the same URL, Squid just sends the first of them. The other, so
5377# called "collapsed" requests, wait for the response to the first
5378# request and, if it happens to be cachable, use that response.
5379# Here, "concurrent requests" means "received after the first
5380# request headers were parsed and before the corresponding response
5381# headers were parsed".
5382#
5383# This feature is disabled by default: enabling collapsed
5384# forwarding needlessly delays forwarding requests that look
5385# cachable (when they are collapsed) but then need to be forwarded
5386# individually anyway because they end up being for uncachable
5387# content. However, in some cases, such as acceleration of highly
5388# cachable content with periodic or grouped expiration times, the
5389# gains from collapsing [large volumes of simultaneous refresh
5390# requests] outweigh losses from such delays.
5391#
5392# Squid collapses two kinds of requests: regular client requests
5393# received on one of the listening ports and internal "cache
5394# revalidation" requests which are triggered by those regular
5395# requests hitting a stale cached object. Revalidation collapsing
5396# is currently disabled for Squid instances containing SMP-aware
5397# disk or memory caches and for Vary-controlled cached objects.
5398#Default:
5399# collapsed_forwarding off
5400
5401# TIMEOUTS
5402# -----------------------------------------------------------------------------
5403
5404# TAG: forward_timeout time-units
5405# This parameter specifies how long Squid should at most attempt in
5406# finding a forwarding path for the request before giving up.
5407#Default:
5408# forward_timeout 4 minutes
5409
5410# TAG: connect_timeout time-units
5411# This parameter specifies how long to wait for the TCP connect to
5412# the requested server or peer to complete before Squid should
5413# attempt to find another path where to forward the request.
5414#Default:
5415# connect_timeout 1 minute
5416
5417# TAG: peer_connect_timeout time-units
5418# This parameter specifies how long to wait for a pending TCP
5419# connection to a peer cache. The default is 30 seconds. You
5420# may also set different timeout values for individual neighbors
5421# with the 'connect-timeout' option on a 'cache_peer' line.
5422#Default:
5423# peer_connect_timeout 30 seconds
5424
5425# TAG: read_timeout time-units
5426# Applied on peer server connections.
5427#
5428# After each successful read(), the timeout will be extended by this
5429# amount. If no data is read again after this amount of time,
5430# the request is aborted and logged with ERR_READ_TIMEOUT.
5431#
5432# The default is 15 minutes.
5433#Default:
5434# read_timeout 15 minutes
5435
5436# TAG: write_timeout time-units
5437# This timeout is tracked for all connections that have data
5438# available for writing and are waiting for the socket to become
5439# ready. After each successful write, the timeout is extended by
5440# the configured amount. If Squid has data to write but the
5441# connection is not ready for the configured duration, the
5442# transaction associated with the connection is terminated. The
5443# default is 15 minutes.
5444#Default:
5445# write_timeout 15 minutes
5446
5447# TAG: request_timeout
5448# How long to wait for complete HTTP request headers after initial
5449# connection establishment.
5450#Default:
5451# request_timeout 5 minutes
5452
5453# TAG: client_idle_pconn_timeout
5454# How long to wait for the next HTTP request on a persistent
5455# client connection after the previous request completes.
5456#Default:
5457# client_idle_pconn_timeout 2 minutes
5458
5459# TAG: ftp_client_idle_timeout
5460# How long to wait for an FTP request on a connection to Squid ftp_port.
5461# Many FTP clients do not deal with idle connection closures well,
5462# necessitating a longer default timeout than client_idle_pconn_timeout
5463# used for incoming HTTP requests.
5464#Default:
5465# ftp_client_idle_timeout 30 minutes
5466
5467# TAG: client_lifetime time-units
5468# The maximum amount of time a client (browser) is allowed to
5469# remain connected to the cache process. This protects the Cache
5470# from having a lot of sockets (and hence file descriptors) tied up
5471# in a CLOSE_WAIT state from remote clients that go away without
5472# properly shutting down (either because of a network failure or
5473# because of a poor client implementation). The default is one
5474# day, 1440 minutes.
5475#
5476# NOTE: The default value is intended to be much larger than any
5477# client would ever need to be connected to your cache. You
5478# should probably change client_lifetime only as a last resort.
5479# If you seem to have many client connections tying up
5480# filedescriptors, we recommend first tuning the read_timeout,
5481# request_timeout, persistent_request_timeout and quick_abort values.
5482#Default:
5483# client_lifetime 1 day
5484
5485# TAG: half_closed_clients
5486# Some clients may shutdown the sending side of their TCP
5487# connections, while leaving their receiving sides open. Sometimes,
5488# Squid can not tell the difference between a half-closed and a
5489# fully-closed TCP connection.
5490#
5491# By default, Squid will immediately close client connections when
5492# read(2) returns "no more data to read."
5493#
5494# Change this option to 'on' and Squid will keep open connections
5495# until a read(2) or write(2) on the socket returns an error.
5496# This may show some benefits for reverse proxies. But if not
5497# it is recommended to leave OFF.
5498#Default:
5499# half_closed_clients off
5500
5501# TAG: server_idle_pconn_timeout
5502# Timeout for idle persistent connections to servers and other
5503# proxies.
5504#Default:
5505# server_idle_pconn_timeout 1 minute
5506
5507# TAG: ident_timeout
5508# Maximum time to wait for IDENT lookups to complete.
5509#
5510# If this is too high, and you enabled IDENT lookups from untrusted
5511# users, you might be susceptible to denial-of-service by having
5512# many ident requests going at once.
5513#Default:
5514# ident_timeout 10 seconds
5515
5516# TAG: shutdown_lifetime time-units
5517# When SIGTERM or SIGHUP is received, the cache is put into
5518# "shutdown pending" mode until all active sockets are closed.
5519# This value is the lifetime to set for all open descriptors
5520# during shutdown mode. Any active clients after this many
5521# seconds will receive a 'timeout' message.
5522#Default:
5523# shutdown_lifetime 30 seconds
5524
5525# ADMINISTRATIVE PARAMETERS
5526# -----------------------------------------------------------------------------
5527
5528# TAG: cache_mgr
5529# Email-address of local cache manager who will receive
5530# mail if the cache dies. The default is "webmaster".
5531#Default:
5532# cache_mgr webmaster
5533
5534# TAG: mail_from
5535# From: email-address for mail sent when the cache dies.
5536# The default is to use 'squid@unique_hostname'.
5537#
5538# See also: unique_hostname directive.
5539#Default:
5540# none
5541
5542# TAG: mail_program
5543# Email program used to send mail if the cache dies.
5544# The default is "mail". The specified program must comply
5545# with the standard Unix mail syntax:
5546# mail-program recipient < mailfile
5547#
5548# Optional command line options can be specified.
5549#Default:
5550# mail_program mail
5551
5552# TAG: cache_effective_user
5553# If you start Squid as root, it will change its effective/real
5554# UID/GID to the user specified below. The default is to change
5555# to UID of proxy.
5556# see also; cache_effective_group
5557#Default:
5558# cache_effective_user proxy
5559
5560# TAG: cache_effective_group
5561# Squid sets the GID to the effective user's default group ID
5562# (taken from the password file) and supplementary group list
5563# from the groups membership.
5564#
5565# If you want Squid to run with a specific GID regardless of
5566# the group memberships of the effective user then set this
5567# to the group (or GID) you want Squid to run as. When set
5568# all other group privileges of the effective user are ignored
5569# and only this GID is effective. If Squid is not started as
5570# root the user starting Squid MUST be member of the specified
5571# group.
5572#
5573# This option is not recommended by the Squid Team.
5574# Our preference is for administrators to configure a secure
5575# user account for squid with UID/GID matching system policies.
5576#Default:
5577# Use system group memberships of the cache_effective_user account
5578
5579# TAG: httpd_suppress_version_string on|off
5580# Suppress Squid version string info in HTTP headers and HTML error pages.
5581#Default:
5582# httpd_suppress_version_string off
5583
5584# TAG: visible_hostname
5585# If you want to present a special hostname in error messages, etc,
5586# define this. Otherwise, the return value of gethostname()
5587# will be used. If you have multiple caches in a cluster and
5588# get errors about IP-forwarding you must set them to have individual
5589# names with this setting.
5590#Default:
5591# Automatically detect the system host name
5592
5593# TAG: unique_hostname
5594# If you want to have multiple machines with the same
5595# 'visible_hostname' you must give each machine a different
5596# 'unique_hostname' so forwarding loops can be detected.
5597#Default:
5598# Copy the value from visible_hostname
5599
5600# TAG: hostname_aliases
5601# A list of other DNS names your cache has.
5602#Default:
5603# none
5604
5605# TAG: umask
5606# Minimum umask which should be enforced while the proxy
5607# is running, in addition to the umask set at startup.
5608#
5609# For a traditional octal representation of umasks, start
5610# your value with 0.
5611#Default:
5612# umask 027
5613
5614# OPTIONS FOR THE CACHE REGISTRATION SERVICE
5615# -----------------------------------------------------------------------------
5616#
5617# This section contains parameters for the (optional) cache
5618# announcement service. This service is provided to help
5619# cache administrators locate one another in order to join or
5620# create cache hierarchies.
5621#
5622# An 'announcement' message is sent (via UDP) to the registration
5623# service by Squid. By default, the announcement message is NOT
5624# SENT unless you enable it with 'announce_period' below.
5625#
5626# The announcement message includes your hostname, plus the
5627# following information from this configuration file:
5628#
5629# http_port
5630# icp_port
5631# cache_mgr
5632#
5633# All current information is processed regularly and made
5634# available on the Web at http://www.ircache.net/Cache/Tracker/.
5635
5636# TAG: announce_period
5637# This is how frequently to send cache announcements.
5638#
5639# To enable announcing your cache, just set an announce period.
5640#
5641# Example:
5642# announce_period 1 day
5643#Default:
5644# Announcement messages disabled.
5645
5646# TAG: announce_host
5647# Set the hostname where announce registration messages will be sent.
5648#
5649# See also announce_port and announce_file
5650#Default:
5651# announce_host tracker.ircache.net
5652
5653# TAG: announce_file
5654# The contents of this file will be included in the announce
5655# registration messages.
5656#Default:
5657# none
5658
5659# TAG: announce_port
5660# Set the port where announce registration messages will be sent.
5661#
5662# See also announce_host and announce_file
5663#Default:
5664# announce_port 3131
5665
5666# HTTPD-ACCELERATOR OPTIONS
5667# -----------------------------------------------------------------------------
5668
5669# TAG: httpd_accel_surrogate_id
5670# Surrogates (http://www.esi.org/architecture_spec_1.0.html)
5671# need an identification token to allow control targeting. Because
5672# a farm of surrogates may all perform the same tasks, they may share
5673# an identification token.
5674#Default:
5675# visible_hostname is used if no specific ID is set.
5676
5677# TAG: http_accel_surrogate_remote on|off
5678# Remote surrogates (such as those in a CDN) honour the header
5679# "Surrogate-Control: no-store-remote".
5680#
5681# Set this to on to have squid behave as a remote surrogate.
5682#Default:
5683# http_accel_surrogate_remote off
5684
5685# TAG: esi_parser libxml2|expat|custom
5686# ESI markup is not strictly XML compatible. The custom ESI parser
5687# will give higher performance, but cannot handle non ASCII character
5688# encodings.
5689#Default:
5690# esi_parser custom
5691
5692# DELAY POOL PARAMETERS
5693# -----------------------------------------------------------------------------
5694
5695# TAG: delay_pools
5696# This represents the number of delay pools to be used. For example,
5697# if you have one class 2 delay pool and one class 3 delays pool, you
5698# have a total of 2 delay pools.
5699#
5700# See also delay_parameters, delay_class, delay_access for pool
5701# configuration details.
5702#Default:
5703# delay_pools 0
5704
5705# TAG: delay_class
5706# This defines the class of each delay pool. There must be exactly one
5707# delay_class line for each delay pool. For example, to define two
5708# delay pools, one of class 2 and one of class 3, the settings above
5709# and here would be:
5710#
5711# Example:
5712# delay_pools 4 # 4 delay pools
5713# delay_class 1 2 # pool 1 is a class 2 pool
5714# delay_class 2 3 # pool 2 is a class 3 pool
5715# delay_class 3 4 # pool 3 is a class 4 pool
5716# delay_class 4 5 # pool 4 is a class 5 pool
5717#
5718# The delay pool classes are:
5719#
5720# class 1 Everything is limited by a single aggregate
5721# bucket.
5722#
5723# class 2 Everything is limited by a single aggregate
5724# bucket as well as an "individual" bucket chosen
5725# from bits 25 through 32 of the IPv4 address.
5726#
5727# class 3 Everything is limited by a single aggregate
5728# bucket as well as a "network" bucket chosen
5729# from bits 17 through 24 of the IP address and a
5730# "individual" bucket chosen from bits 17 through
5731# 32 of the IPv4 address.
5732#
5733# class 4 Everything in a class 3 delay pool, with an
5734# additional limit on a per user basis. This
5735# only takes effect if the username is established
5736# in advance - by forcing authentication in your
5737# http_access rules.
5738#
5739# class 5 Requests are grouped according their tag (see
5740# external_acl's tag= reply).
5741#
5742#
5743# Each pool also requires a delay_parameters directive to configure the pool size
5744# and speed limits used whenever the pool is applied to a request. Along with
5745# a set of delay_access directives to determine when it is used.
5746#
5747# NOTE: If an IP address is a.b.c.d
5748# -> bits 25 through 32 are "d"
5749# -> bits 17 through 24 are "c"
5750# -> bits 17 through 32 are "c * 256 + d"
5751#
5752# NOTE-2: Due to the use of bitmasks in class 2,3,4 pools they only apply to
5753# IPv4 traffic. Class 1 and 5 pools may be used with IPv6 traffic.
5754#
5755# This clause only supports fast acl types.
5756# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
5757#
5758# See also delay_parameters and delay_access.
5759#Default:
5760# none
5761
5762# TAG: delay_access
5763# This is used to determine which delay pool a request falls into.
5764#
5765# delay_access is sorted per pool and the matching starts with pool 1,
5766# then pool 2, ..., and finally pool N. The first delay pool where the
5767# request is allowed is selected for the request. If it does not allow
5768# the request to any pool then the request is not delayed (default).
5769#
5770# For example, if you want some_big_clients in delay
5771# pool 1 and lotsa_little_clients in delay pool 2:
5772#
5773# delay_access 1 allow some_big_clients
5774# delay_access 1 deny all
5775# delay_access 2 allow lotsa_little_clients
5776# delay_access 2 deny all
5777# delay_access 3 allow authenticated_clients
5778#
5779# See also delay_parameters and delay_class.
5780#
5781#Default:
5782# Deny using the pool, unless allow rules exist in squid.conf for the pool.
5783
5784# TAG: delay_parameters
5785# This defines the parameters for a delay pool. Each delay pool has
5786# a number of "buckets" associated with it, as explained in the
5787# description of delay_class.
5788#
5789# For a class 1 delay pool, the syntax is:
5790# delay_class pool 1
5791# delay_parameters pool aggregate
5792#
5793# For a class 2 delay pool:
5794# delay_class pool 2
5795# delay_parameters pool aggregate individual
5796#
5797# For a class 3 delay pool:
5798# delay_class pool 3
5799# delay_parameters pool aggregate network individual
5800#
5801# For a class 4 delay pool:
5802# delay_class pool 4
5803# delay_parameters pool aggregate network individual user
5804#
5805# For a class 5 delay pool:
5806# delay_class pool 5
5807# delay_parameters pool tagrate
5808#
5809# The option variables are:
5810#
5811# pool a pool number - ie, a number between 1 and the
5812# number specified in delay_pools as used in
5813# delay_class lines.
5814#
5815# aggregate the speed limit parameters for the aggregate bucket
5816# (class 1, 2, 3).
5817#
5818# individual the speed limit parameters for the individual
5819# buckets (class 2, 3).
5820#
5821# network the speed limit parameters for the network buckets
5822# (class 3).
5823#
5824# user the speed limit parameters for the user buckets
5825# (class 4).
5826#
5827# tagrate the speed limit parameters for the tag buckets
5828# (class 5).
5829#
5830# A pair of delay parameters is written restore/maximum, where restore is
5831# the number of bytes (not bits - modem and network speeds are usually
5832# quoted in bits) per second placed into the bucket, and maximum is the
5833# maximum number of bytes which can be in the bucket at any time.
5834#
5835# There must be one delay_parameters line for each delay pool.
5836#
5837#
5838# For example, if delay pool number 1 is a class 2 delay pool as in the
5839# above example, and is being used to strictly limit each host to 64Kbit/sec
5840# (plus overheads), with no overall limit, the line is:
5841#
5842# delay_parameters 1 none 8000/8000
5843#
5844# Note that 8 x 8K Byte/sec -> 64K bit/sec.
5845#
5846# Note that the word 'none' is used to represent no limit.
5847#
5848#
5849# And, if delay pool number 2 is a class 3 delay pool as in the above
5850# example, and you want to limit it to a total of 256Kbit/sec (strict limit)
5851# with each 8-bit network permitted 64Kbit/sec (strict limit) and each
5852# individual host permitted 4800bit/sec with a bucket maximum size of 64Kbits
5853# to permit a decent web page to be downloaded at a decent speed
5854# (if the network is not being limited due to overuse) but slow down
5855# large downloads more significantly:
5856#
5857# delay_parameters 2 32000/32000 8000/8000 600/8000
5858#
5859# Note that 8 x 32K Byte/sec -> 256K bit/sec.
5860# 8 x 8K Byte/sec -> 64K bit/sec.
5861# 8 x 600 Byte/sec -> 4800 bit/sec.
5862#
5863#
5864# Finally, for a class 4 delay pool as in the example - each user will
5865# be limited to 128Kbits/sec no matter how many workstations they are logged into.:
5866#
5867# delay_parameters 4 32000/32000 8000/8000 600/64000 16000/16000
5868#
5869#
5870# See also delay_class and delay_access.
5871#
5872#Default:
5873# none
5874
5875# TAG: delay_initial_bucket_level (percent, 0-100)
5876# The initial bucket percentage is used to determine how much is put
5877# in each bucket when squid starts, is reconfigured, or first notices
5878# a host accessing it (in class 2 and class 3, individual hosts and
5879# networks only have buckets associated with them once they have been
5880# "seen" by squid).
5881#Default:
5882# delay_initial_bucket_level 50
5883
5884# CLIENT DELAY POOL PARAMETERS
5885# -----------------------------------------------------------------------------
5886
5887# TAG: client_delay_pools
5888# This option specifies the number of client delay pools used. It must
5889# preceed other client_delay_* options.
5890#
5891# Example:
5892# client_delay_pools 2
5893#
5894# See also client_delay_parameters and client_delay_access.
5895#Default:
5896# client_delay_pools 0
5897
5898# TAG: client_delay_initial_bucket_level (percent, 0-no_limit)
5899# This option determines the initial bucket size as a percentage of
5900# max_bucket_size from client_delay_parameters. Buckets are created
5901# at the time of the "first" connection from the matching IP. Idle
5902# buckets are periodically deleted up.
5903#
5904# You can specify more than 100 percent but note that such "oversized"
5905# buckets are not refilled until their size goes down to max_bucket_size
5906# from client_delay_parameters.
5907#
5908# Example:
5909# client_delay_initial_bucket_level 50
5910#Default:
5911# client_delay_initial_bucket_level 50
5912
5913# TAG: client_delay_parameters
5914#
5915# This option configures client-side bandwidth limits using the
5916# following format:
5917#
5918# client_delay_parameters pool speed_limit max_bucket_size
5919#
5920# pool is an integer ID used for client_delay_access matching.
5921#
5922# speed_limit is bytes added to the bucket per second.
5923#
5924# max_bucket_size is the maximum size of a bucket, enforced after any
5925# speed_limit additions.
5926#
5927# Please see the delay_parameters option for more information and
5928# examples.
5929#
5930# Example:
5931# client_delay_parameters 1 1024 2048
5932# client_delay_parameters 2 51200 16384
5933#
5934# See also client_delay_access.
5935#
5936#Default:
5937# none
5938
5939# TAG: client_delay_access
5940# This option determines the client-side delay pool for the
5941# request:
5942#
5943# client_delay_access pool_ID allow|deny acl_name
5944#
5945# All client_delay_access options are checked in their pool ID
5946# order, starting with pool 1. The first checked pool with allowed
5947# request is selected for the request. If no ACL matches or there
5948# are no client_delay_access options, the request bandwidth is not
5949# limited.
5950#
5951# The ACL-selected pool is then used to find the
5952# client_delay_parameters for the request. Client-side pools are
5953# not used to aggregate clients. Clients are always aggregated
5954# based on their source IP addresses (one bucket per source IP).
5955#
5956# This clause only supports fast acl types.
5957# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
5958# Additionally, only the client TCP connection details are available.
5959# ACLs testing HTTP properties will not work.
5960#
5961# Please see delay_access for more examples.
5962#
5963# Example:
5964# client_delay_access 1 allow low_rate_network
5965# client_delay_access 2 allow vips_network
5966#
5967#
5968# See also client_delay_parameters and client_delay_pools.
5969#Default:
5970# Deny use of the pool, unless allow rules exist in squid.conf for the pool.
5971
5972# WCCPv1 AND WCCPv2 CONFIGURATION OPTIONS
5973# -----------------------------------------------------------------------------
5974
5975# TAG: wccp_router
5976# Use this option to define your WCCP ``home'' router for
5977# Squid.
5978#
5979# wccp_router supports a single WCCP(v1) router
5980#
5981# wccp2_router supports multiple WCCPv2 routers
5982#
5983# only one of the two may be used at the same time and defines
5984# which version of WCCP to use.
5985#Default:
5986# WCCP disabled.
5987
5988# TAG: wccp2_router
5989# Use this option to define your WCCP ``home'' router for
5990# Squid.
5991#
5992# wccp_router supports a single WCCP(v1) router
5993#
5994# wccp2_router supports multiple WCCPv2 routers
5995#
5996# only one of the two may be used at the same time and defines
5997# which version of WCCP to use.
5998#Default:
5999# WCCPv2 disabled.
6000
6001# TAG: wccp_version
6002# This directive is only relevant if you need to set up WCCP(v1)
6003# to some very old and end-of-life Cisco routers. In all other
6004# setups it must be left unset or at the default setting.
6005# It defines an internal version in the WCCP(v1) protocol,
6006# with version 4 being the officially documented protocol.
6007#
6008# According to some users, Cisco IOS 11.2 and earlier only
6009# support WCCP version 3. If you're using that or an earlier
6010# version of IOS, you may need to change this value to 3, otherwise
6011# do not specify this parameter.
6012#Default:
6013# wccp_version 4
6014
6015# TAG: wccp2_rebuild_wait
6016# If this is enabled Squid will wait for the cache dir rebuild to finish
6017# before sending the first wccp2 HereIAm packet
6018#Default:
6019# wccp2_rebuild_wait on
6020
6021# TAG: wccp2_forwarding_method
6022# WCCP2 allows the setting of forwarding methods between the
6023# router/switch and the cache. Valid values are as follows:
6024#
6025# gre - GRE encapsulation (forward the packet in a GRE/WCCP tunnel)
6026# l2 - L2 redirect (forward the packet using Layer 2/MAC rewriting)
6027#
6028# Currently (as of IOS 12.4) cisco routers only support GRE.
6029# Cisco switches only support the L2 redirect assignment method.
6030#Default:
6031# wccp2_forwarding_method gre
6032
6033# TAG: wccp2_return_method
6034# WCCP2 allows the setting of return methods between the
6035# router/switch and the cache for packets that the cache
6036# decides not to handle. Valid values are as follows:
6037#
6038# gre - GRE encapsulation (forward the packet in a GRE/WCCP tunnel)
6039# l2 - L2 redirect (forward the packet using Layer 2/MAC rewriting)
6040#
6041# Currently (as of IOS 12.4) cisco routers only support GRE.
6042# Cisco switches only support the L2 redirect assignment.
6043#
6044# If the "ip wccp redirect exclude in" command has been
6045# enabled on the cache interface, then it is still safe for
6046# the proxy server to use a l2 redirect method even if this
6047# option is set to GRE.
6048#Default:
6049# wccp2_return_method gre
6050
6051# TAG: wccp2_assignment_method
6052# WCCP2 allows the setting of methods to assign the WCCP hash
6053# Valid values are as follows:
6054#
6055# hash - Hash assignment
6056# mask - Mask assignment
6057#
6058# As a general rule, cisco routers support the hash assignment method
6059# and cisco switches support the mask assignment method.
6060#Default:
6061# wccp2_assignment_method hash
6062
6063# TAG: wccp2_service
6064# WCCP2 allows for multiple traffic services. There are two
6065# types: "standard" and "dynamic". The standard type defines
6066# one service id - http (id 0). The dynamic service ids can be from
6067# 51 to 255 inclusive. In order to use a dynamic service id
6068# one must define the type of traffic to be redirected; this is done
6069# using the wccp2_service_info option.
6070#
6071# The "standard" type does not require a wccp2_service_info option,
6072# just specifying the service id will suffice.
6073#
6074# MD5 service authentication can be enabled by adding
6075# "password=<password>" to the end of this service declaration.
6076#
6077# Examples:
6078#
6079# wccp2_service standard 0 # for the 'web-cache' standard service
6080# wccp2_service dynamic 80 # a dynamic service type which will be
6081# # fleshed out with subsequent options.
6082# wccp2_service standard 0 password=foo
6083#Default:
6084# Use the 'web-cache' standard service.
6085
6086# TAG: wccp2_service_info
6087# Dynamic WCCPv2 services require further information to define the
6088# traffic you wish to have diverted.
6089#
6090# The format is:
6091#
6092# wccp2_service_info <id> protocol=<protocol> flags=<flag>,<flag>..
6093# priority=<priority> ports=<port>,<port>..
6094#
6095# The relevant WCCPv2 flags:
6096# + src_ip_hash, dst_ip_hash
6097# + source_port_hash, dst_port_hash
6098# + src_ip_alt_hash, dst_ip_alt_hash
6099# + src_port_alt_hash, dst_port_alt_hash
6100# + ports_source
6101#
6102# The port list can be one to eight entries.
6103#
6104# Example:
6105#
6106# wccp2_service_info 80 protocol=tcp flags=src_ip_hash,ports_source
6107# priority=240 ports=80
6108#
6109# Note: the service id must have been defined by a previous
6110# 'wccp2_service dynamic <id>' entry.
6111#Default:
6112# none
6113
6114# TAG: wccp2_weight
6115# Each cache server gets assigned a set of the destination
6116# hash proportional to their weight.
6117#Default:
6118# wccp2_weight 10000
6119
6120# TAG: wccp_address
6121# Use this option if you require WCCPv2 to use a specific
6122# interface address.
6123#
6124# The default behavior is to not bind to any specific address.
6125#Default:
6126# Address selected by the operating system.
6127
6128# TAG: wccp2_address
6129# Use this option if you require WCCP to use a specific
6130# interface address.
6131#
6132# The default behavior is to not bind to any specific address.
6133#Default:
6134# Address selected by the operating system.
6135
6136# PERSISTENT CONNECTION HANDLING
6137# -----------------------------------------------------------------------------
6138#
6139# Also see "pconn_timeout" in the TIMEOUTS section
6140
6141# TAG: client_persistent_connections
6142# Persistent connection support for clients.
6143# Squid uses persistent connections (when allowed). You can use
6144# this option to disable persistent connections with clients.
6145#Default:
6146# client_persistent_connections on
6147
6148# TAG: server_persistent_connections
6149# Persistent connection support for servers.
6150# Squid uses persistent connections (when allowed). You can use
6151# this option to disable persistent connections with servers.
6152#Default:
6153# server_persistent_connections on
6154
6155# TAG: persistent_connection_after_error
6156# With this directive the use of persistent connections after
6157# HTTP errors can be disabled. Useful if you have clients
6158# who fail to handle errors on persistent connections proper.
6159#Default:
6160# persistent_connection_after_error on
6161
6162# TAG: detect_broken_pconn
6163# Some servers have been found to incorrectly signal the use
6164# of HTTP/1.0 persistent connections even on replies not
6165# compatible, causing significant delays. This server problem
6166# has mostly been seen on redirects.
6167#
6168# By enabling this directive Squid attempts to detect such
6169# broken replies and automatically assume the reply is finished
6170# after 10 seconds timeout.
6171#Default:
6172# detect_broken_pconn off
6173
6174# CACHE DIGEST OPTIONS
6175# -----------------------------------------------------------------------------
6176
6177# TAG: digest_generation
6178# This controls whether the server will generate a Cache Digest
6179# of its contents. By default, Cache Digest generation is
6180# enabled if Squid is compiled with --enable-cache-digests defined.
6181#Default:
6182# digest_generation on
6183
6184# TAG: digest_bits_per_entry
6185# This is the number of bits of the server's Cache Digest which
6186# will be associated with the Digest entry for a given HTTP
6187# Method and URL (public key) combination. The default is 5.
6188#Default:
6189# digest_bits_per_entry 5
6190
6191# TAG: digest_rebuild_period (seconds)
6192# This is the wait time between Cache Digest rebuilds.
6193#Default:
6194# digest_rebuild_period 1 hour
6195
6196# TAG: digest_rewrite_period (seconds)
6197# This is the wait time between Cache Digest writes to
6198# disk.
6199#Default:
6200# digest_rewrite_period 1 hour
6201
6202# TAG: digest_swapout_chunk_size (bytes)
6203# This is the number of bytes of the Cache Digest to write to
6204# disk at a time. It defaults to 4096 bytes (4KB), the Squid
6205# default swap page.
6206#Default:
6207# digest_swapout_chunk_size 4096 bytes
6208
6209# TAG: digest_rebuild_chunk_percentage (percent, 0-100)
6210# This is the percentage of the Cache Digest to be scanned at a
6211# time. By default it is set to 10% of the Cache Digest.
6212#Default:
6213# digest_rebuild_chunk_percentage 10
6214
6215# SNMP OPTIONS
6216# -----------------------------------------------------------------------------
6217
6218# TAG: snmp_port
6219# The port number where Squid listens for SNMP requests. To enable
6220# SNMP support set this to a suitable port number. Port number
6221# 3401 is often used for the Squid SNMP agent. By default it's
6222# set to "0" (disabled)
6223#
6224# Example:
6225# snmp_port 3401
6226#Default:
6227# SNMP disabled.
6228
6229# TAG: snmp_access
6230# Allowing or denying access to the SNMP port.
6231#
6232# All access to the agent is denied by default.
6233# usage:
6234#
6235# snmp_access allow|deny [!]aclname ...
6236#
6237# This clause only supports fast acl types.
6238# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
6239#
6240#Example:
6241# snmp_access allow snmppublic localhost
6242# snmp_access deny all
6243#Default:
6244# Deny, unless rules exist in squid.conf.
6245
6246# TAG: snmp_incoming_address
6247# Just like 'udp_incoming_address', but for the SNMP port.
6248#
6249# snmp_incoming_address is used for the SNMP socket receiving
6250# messages from SNMP agents.
6251#
6252# The default snmp_incoming_address is to listen on all
6253# available network interfaces.
6254#Default:
6255# Accept SNMP packets from all machine interfaces.
6256
6257# TAG: snmp_outgoing_address
6258# Just like 'udp_outgoing_address', but for the SNMP port.
6259#
6260# snmp_outgoing_address is used for SNMP packets returned to SNMP
6261# agents.
6262#
6263# If snmp_outgoing_address is not set it will use the same socket
6264# as snmp_incoming_address. Only change this if you want to have
6265# SNMP replies sent using another address than where this Squid
6266# listens for SNMP queries.
6267#
6268# NOTE, snmp_incoming_address and snmp_outgoing_address can not have
6269# the same value since they both use the same port.
6270#Default:
6271# Use snmp_incoming_address or an address selected by the operating system.
6272
6273# ICP OPTIONS
6274# -----------------------------------------------------------------------------
6275
6276# TAG: icp_port
6277# The port number where Squid sends and receives ICP queries to
6278# and from neighbor caches. The standard UDP port for ICP is 3130.
6279#
6280# Example:
6281# icp_port 3130
6282#Default:
6283# ICP disabled.
6284
6285# TAG: htcp_port
6286# The port number where Squid sends and receives HTCP queries to
6287# and from neighbor caches. To turn it on you want to set it to
6288# 4827.
6289#
6290# Example:
6291# htcp_port 4827
6292#Default:
6293# HTCP disabled.
6294
6295# TAG: log_icp_queries on|off
6296# If set, ICP queries are logged to access.log. You may wish
6297# do disable this if your ICP load is VERY high to speed things
6298# up or to simplify log analysis.
6299#Default:
6300# log_icp_queries on
6301
6302# TAG: udp_incoming_address
6303# udp_incoming_address is used for UDP packets received from other
6304# caches.
6305#
6306# The default behavior is to not bind to any specific address.
6307#
6308# Only change this if you want to have all UDP queries received on
6309# a specific interface/address.
6310#
6311# NOTE: udp_incoming_address is used by the ICP, HTCP, and DNS
6312# modules. Altering it will affect all of them in the same manner.
6313#
6314# see also; udp_outgoing_address
6315#
6316# NOTE, udp_incoming_address and udp_outgoing_address can not
6317# have the same value since they both use the same port.
6318#Default:
6319# Accept packets from all machine interfaces.
6320
6321# TAG: udp_outgoing_address
6322# udp_outgoing_address is used for UDP packets sent out to other
6323# caches.
6324#
6325# The default behavior is to not bind to any specific address.
6326#
6327# Instead it will use the same socket as udp_incoming_address.
6328# Only change this if you want to have UDP queries sent using another
6329# address than where this Squid listens for UDP queries from other
6330# caches.
6331#
6332# NOTE: udp_outgoing_address is used by the ICP, HTCP, and DNS
6333# modules. Altering it will affect all of them in the same manner.
6334#
6335# see also; udp_incoming_address
6336#
6337# NOTE, udp_incoming_address and udp_outgoing_address can not
6338# have the same value since they both use the same port.
6339#Default:
6340# Use udp_incoming_address or an address selected by the operating system.
6341
6342# TAG: icp_hit_stale on|off
6343# If you want to return ICP_HIT for stale cache objects, set this
6344# option to 'on'. If you have sibling relationships with caches
6345# in other administrative domains, this should be 'off'. If you only
6346# have sibling relationships with caches under your control,
6347# it is probably okay to set this to 'on'.
6348# If set to 'on', your siblings should use the option "allow-miss"
6349# on their cache_peer lines for connecting to you.
6350#Default:
6351# icp_hit_stale off
6352
6353# TAG: minimum_direct_hops
6354# If using the ICMP pinging stuff, do direct fetches for sites
6355# which are no more than this many hops away.
6356#Default:
6357# minimum_direct_hops 4
6358
6359# TAG: minimum_direct_rtt (msec)
6360# If using the ICMP pinging stuff, do direct fetches for sites
6361# which are no more than this many rtt milliseconds away.
6362#Default:
6363# minimum_direct_rtt 400
6364
6365# TAG: netdb_low
6366# The low water mark for the ICMP measurement database.
6367#
6368# Note: high watermark controlled by netdb_high directive.
6369#
6370# These watermarks are counts, not percents. The defaults are
6371# (low) 900 and (high) 1000. When the high water mark is
6372# reached, database entries will be deleted until the low
6373# mark is reached.
6374#Default:
6375# netdb_low 900
6376
6377# TAG: netdb_high
6378# The high water mark for the ICMP measurement database.
6379#
6380# Note: low watermark controlled by netdb_low directive.
6381#
6382# These watermarks are counts, not percents. The defaults are
6383# (low) 900 and (high) 1000. When the high water mark is
6384# reached, database entries will be deleted until the low
6385# mark is reached.
6386#Default:
6387# netdb_high 1000
6388
6389# TAG: netdb_ping_period
6390# The minimum period for measuring a site. There will be at
6391# least this much delay between successive pings to the same
6392# network. The default is five minutes.
6393#Default:
6394# netdb_ping_period 5 minutes
6395
6396# TAG: query_icmp on|off
6397# If you want to ask your peers to include ICMP data in their ICP
6398# replies, enable this option.
6399#
6400# If your peer has configured Squid (during compilation) with
6401# '--enable-icmp' that peer will send ICMP pings to origin server
6402# sites of the URLs it receives. If you enable this option the
6403# ICP replies from that peer will include the ICMP data (if available).
6404# Then, when choosing a parent cache, Squid will choose the parent with
6405# the minimal RTT to the origin server. When this happens, the
6406# hierarchy field of the access.log will be
6407# "CLOSEST_PARENT_MISS". This option is off by default.
6408#Default:
6409# query_icmp off
6410
6411# TAG: test_reachability on|off
6412# When this is 'on', ICP MISS replies will be ICP_MISS_NOFETCH
6413# instead of ICP_MISS if the target host is NOT in the ICMP
6414# database, or has a zero RTT.
6415#Default:
6416# test_reachability off
6417
6418# TAG: icp_query_timeout (msec)
6419# Normally Squid will automatically determine an optimal ICP
6420# query timeout value based on the round-trip-time of recent ICP
6421# queries. If you want to override the value determined by
6422# Squid, set this 'icp_query_timeout' to a non-zero value. This
6423# value is specified in MILLISECONDS, so, to use a 2-second
6424# timeout (the old default), you would write:
6425#
6426# icp_query_timeout 2000
6427#Default:
6428# Dynamic detection.
6429
6430# TAG: maximum_icp_query_timeout (msec)
6431# Normally the ICP query timeout is determined dynamically. But
6432# sometimes it can lead to very large values (say 5 seconds).
6433# Use this option to put an upper limit on the dynamic timeout
6434# value. Do NOT use this option to always use a fixed (instead
6435# of a dynamic) timeout value. To set a fixed timeout see the
6436# 'icp_query_timeout' directive.
6437#Default:
6438# maximum_icp_query_timeout 2000
6439
6440# TAG: minimum_icp_query_timeout (msec)
6441# Normally the ICP query timeout is determined dynamically. But
6442# sometimes it can lead to very small timeouts, even lower than
6443# the normal latency variance on your link due to traffic.
6444# Use this option to put an lower limit on the dynamic timeout
6445# value. Do NOT use this option to always use a fixed (instead
6446# of a dynamic) timeout value. To set a fixed timeout see the
6447# 'icp_query_timeout' directive.
6448#Default:
6449# minimum_icp_query_timeout 5
6450
6451# TAG: background_ping_rate time-units
6452# Controls how often the ICP pings are sent to siblings that
6453# have background-ping set.
6454#Default:
6455# background_ping_rate 10 seconds
6456
6457# MULTICAST ICP OPTIONS
6458# -----------------------------------------------------------------------------
6459
6460# TAG: mcast_groups
6461# This tag specifies a list of multicast groups which your server
6462# should join to receive multicasted ICP queries.
6463#
6464# NOTE! Be very careful what you put here! Be sure you
6465# understand the difference between an ICP _query_ and an ICP
6466# _reply_. This option is to be set only if you want to RECEIVE
6467# multicast queries. Do NOT set this option to SEND multicast
6468# ICP (use cache_peer for that). ICP replies are always sent via
6469# unicast, so this option does not affect whether or not you will
6470# receive replies from multicast group members.
6471#
6472# You must be very careful to NOT use a multicast address which
6473# is already in use by another group of caches.
6474#
6475# If you are unsure about multicast, please read the Multicast
6476# chapter in the Squid FAQ (http://www.squid-cache.org/FAQ/).
6477#
6478# Usage: mcast_groups 239.128.16.128 224.0.1.20
6479#
6480# By default, Squid doesn't listen on any multicast groups.
6481#Default:
6482# none
6483
6484# TAG: mcast_miss_addr
6485# Note: This option is only available if Squid is rebuilt with the
6486# -DMULTICAST_MISS_STREAM define
6487#
6488# If you enable this option, every "cache miss" URL will
6489# be sent out on the specified multicast address.
6490#
6491# Do not enable this option unless you are are absolutely
6492# certain you understand what you are doing.
6493#Default:
6494# disabled.
6495
6496# TAG: mcast_miss_ttl
6497# Note: This option is only available if Squid is rebuilt with the
6498# -DMULTICAST_MISS_STREAM define
6499#
6500# This is the time-to-live value for packets multicasted
6501# when multicasting off cache miss URLs is enabled. By
6502# default this is set to 'site scope', i.e. 16.
6503#Default:
6504# mcast_miss_ttl 16
6505
6506# TAG: mcast_miss_port
6507# Note: This option is only available if Squid is rebuilt with the
6508# -DMULTICAST_MISS_STREAM define
6509#
6510# This is the port number to be used in conjunction with
6511# 'mcast_miss_addr'.
6512#Default:
6513# mcast_miss_port 3135
6514
6515# TAG: mcast_miss_encode_key
6516# Note: This option is only available if Squid is rebuilt with the
6517# -DMULTICAST_MISS_STREAM define
6518#
6519# The URLs that are sent in the multicast miss stream are
6520# encrypted. This is the encryption key.
6521#Default:
6522# mcast_miss_encode_key XXXXXXXXXXXXXXXX
6523
6524# TAG: mcast_icp_query_timeout (msec)
6525# For multicast peers, Squid regularly sends out ICP "probes" to
6526# count how many other peers are listening on the given multicast
6527# address. This value specifies how long Squid should wait to
6528# count all the replies. The default is 2000 msec, or 2
6529# seconds.
6530#Default:
6531# mcast_icp_query_timeout 2000
6532
6533# INTERNAL ICON OPTIONS
6534# -----------------------------------------------------------------------------
6535
6536# TAG: icon_directory
6537# Where the icons are stored. These are normally kept in
6538# /usr/share/squid/icons
6539#Default:
6540# icon_directory /usr/share/squid/icons
6541
6542# TAG: global_internal_static
6543# This directive controls is Squid should intercept all requests for
6544# /squid-internal-static/ no matter which host the URL is requesting
6545# (default on setting), or if nothing special should be done for
6546# such URLs (off setting). The purpose of this directive is to make
6547# icons etc work better in complex cache hierarchies where it may
6548# not always be possible for all corners in the cache mesh to reach
6549# the server generating a directory listing.
6550#Default:
6551# global_internal_static on
6552
6553# TAG: short_icon_urls
6554# If this is enabled Squid will use short URLs for icons.
6555# If disabled it will revert to the old behavior of including
6556# it's own name and port in the URL.
6557#
6558# If you run a complex cache hierarchy with a mix of Squid and
6559# other proxies you may need to disable this directive.
6560#Default:
6561# short_icon_urls on
6562
6563# ERROR PAGE OPTIONS
6564# -----------------------------------------------------------------------------
6565
6566# TAG: error_directory
6567# If you wish to create your own versions of the default
6568# error files to customize them to suit your company copy
6569# the error/template files to another directory and point
6570# this tag at them.
6571#
6572# WARNING: This option will disable multi-language support
6573# on error pages if used.
6574#
6575# The squid developers are interested in making squid available in
6576# a wide variety of languages. If you are making translations for a
6577# language that Squid does not currently provide please consider
6578# contributing your translation back to the project.
6579# http://wiki.squid-cache.org/Translations
6580#
6581# The squid developers working on translations are happy to supply drop-in
6582# translated error files in exchange for any new language contributions.
6583#Default:
6584# Send error pages in the clients preferred language
6585
6586# TAG: error_default_language
6587# Set the default language which squid will send error pages in
6588# if no existing translation matches the clients language
6589# preferences.
6590#
6591# If unset (default) generic English will be used.
6592#
6593# The squid developers are interested in making squid available in
6594# a wide variety of languages. If you are interested in making
6595# translations for any language see the squid wiki for details.
6596# http://wiki.squid-cache.org/Translations
6597#Default:
6598# Generate English language pages.
6599
6600# TAG: error_log_languages
6601# Log to cache.log what languages users are attempting to
6602# auto-negotiate for translations.
6603#
6604# Successful negotiations are not logged. Only failures
6605# have meaning to indicate that Squid may need an upgrade
6606# of its error page translations.
6607#Default:
6608# error_log_languages on
6609
6610# TAG: err_page_stylesheet
6611# CSS Stylesheet to pattern the display of Squid default error pages.
6612#
6613# For information on CSS see http://www.w3.org/Style/CSS/
6614#Default:
6615# err_page_stylesheet /etc/squid/errorpage.css
6616
6617# TAG: err_html_text
6618# HTML text to include in error messages. Make this a "mailto"
6619# URL to your admin address, or maybe just a link to your
6620# organizations Web page.
6621#
6622# To include this in your error messages, you must rewrite
6623# the error template files (found in the "errors" directory).
6624# Wherever you want the 'err_html_text' line to appear,
6625# insert a %L tag in the error template file.
6626#Default:
6627# none
6628
6629# TAG: email_err_data on|off
6630# If enabled, information about the occurred error will be
6631# included in the mailto links of the ERR pages (if %W is set)
6632# so that the email body contains the data.
6633# Syntax is <A HREF="mailto:%w%W">%w</A>
6634#Default:
6635# email_err_data on
6636
6637# TAG: deny_info
6638# Usage: deny_info err_page_name acl
6639# or deny_info http://... acl
6640# or deny_info TCP_RESET acl
6641#
6642# This can be used to return a ERR_ page for requests which
6643# do not pass the 'http_access' rules. Squid remembers the last
6644# acl it evaluated in http_access, and if a 'deny_info' line exists
6645# for that ACL Squid returns a corresponding error page.
6646#
6647# The acl is typically the last acl on the http_access deny line which
6648# denied access. The exceptions to this rule are:
6649# - When Squid needs to request authentication credentials. It's then
6650# the first authentication related acl encountered
6651# - When none of the http_access lines matches. It's then the last
6652# acl processed on the last http_access line.
6653# - When the decision to deny access was made by an adaptation service,
6654# the acl name is the corresponding eCAP or ICAP service_name.
6655#
6656# NP: If providing your own custom error pages with error_directory
6657# you may also specify them by your custom file name:
6658# Example: deny_info ERR_CUSTOM_ACCESS_DENIED bad_guys
6659#
6660# By defaut Squid will send "403 Forbidden". A different 4xx or 5xx
6661# may be specified by prefixing the file name with the code and a colon.
6662# e.g. 404:ERR_CUSTOM_ACCESS_DENIED
6663#
6664# Alternatively you can tell Squid to reset the TCP connection
6665# by specifying TCP_RESET.
6666#
6667# Or you can specify an error URL or URL pattern. The browsers will
6668# get redirected to the specified URL after formatting tags have
6669# been replaced. Redirect will be done with 302 or 307 according to
6670# HTTP/1.1 specs. A different 3xx code may be specified by prefixing
6671# the URL. e.g. 303:http://example.com/
6672#
6673# URL FORMAT TAGS:
6674# %a - username (if available. Password NOT included)
6675# %B - FTP path URL
6676# %e - Error number
6677# %E - Error description
6678# %h - Squid hostname
6679# %H - Request domain name
6680# %i - Client IP Address
6681# %M - Request Method
6682# %o - Message result from external ACL helper
6683# %p - Request Port number
6684# %P - Request Protocol name
6685# %R - Request URL path
6686# %T - Timestamp in RFC 1123 format
6687# %U - Full canonical URL from client
6688# (HTTPS URLs terminate with *)
6689# %u - Full canonical URL from client
6690# %w - Admin email from squid.conf
6691# %x - Error name
6692# %% - Literal percent (%) code
6693#
6694#Default:
6695# none
6696
6697# OPTIONS INFLUENCING REQUEST FORWARDING
6698# -----------------------------------------------------------------------------
6699
6700# TAG: nonhierarchical_direct
6701# By default, Squid will send any non-hierarchical requests
6702# (not cacheable request type) direct to origin servers.
6703#
6704# When this is set to "off", Squid will prefer to send these
6705# requests to parents.
6706#
6707# Note that in most configurations, by turning this off you will only
6708# add latency to these request without any improvement in global hit
6709# ratio.
6710#
6711# This option only sets a preference. If the parent is unavailable a
6712# direct connection to the origin server may still be attempted. To
6713# completely prevent direct connections use never_direct.
6714#Default:
6715# nonhierarchical_direct on
6716
6717# TAG: prefer_direct
6718# Normally Squid tries to use parents for most requests. If you for some
6719# reason like it to first try going direct and only use a parent if
6720# going direct fails set this to on.
6721#
6722# By combining nonhierarchical_direct off and prefer_direct on you
6723# can set up Squid to use a parent as a backup path if going direct
6724# fails.
6725#
6726# Note: If you want Squid to use parents for all requests see
6727# the never_direct directive. prefer_direct only modifies how Squid
6728# acts on cacheable requests.
6729#Default:
6730# prefer_direct off
6731
6732# TAG: cache_miss_revalidate on|off
6733# RFC 7232 defines a conditional request mechanism to prevent
6734# response objects being unnecessarily transferred over the network.
6735# If that mechanism is used by the client and a cache MISS occurs
6736# it can prevent new cache entries being created.
6737#
6738# This option determines whether Squid on cache MISS will pass the
6739# client revalidation request to the server or tries to fetch new
6740# content for caching. It can be useful while the cache is mostly
6741# empty to more quickly have the cache populated by generating
6742# non-conditional GETs.
6743#
6744# When set to 'on' (default), Squid will pass all client If-* headers
6745# to the server. This permits server responses without a cacheable
6746# payload to be delivered and on MISS no new cache entry is created.
6747#
6748# When set to 'off' and if the request is cacheable, Squid will
6749# remove the clients If-Modified-Since and If-None-Match headers from
6750# the request sent to the server. This requests a 200 status response
6751# from the server to create a new cache entry with.
6752#Default:
6753# cache_miss_revalidate on
6754
6755# TAG: always_direct
6756# Usage: always_direct allow|deny [!]aclname ...
6757#
6758# Here you can use ACL elements to specify requests which should
6759# ALWAYS be forwarded by Squid to the origin servers without using
6760# any peers. For example, to always directly forward requests for
6761# local servers ignoring any parents or siblings you may have use
6762# something like:
6763#
6764# acl local-servers dstdomain my.domain.net
6765# always_direct allow local-servers
6766#
6767# To always forward FTP requests directly, use
6768#
6769# acl FTP proto FTP
6770# always_direct allow FTP
6771#
6772# NOTE: There is a similar, but opposite option named
6773# 'never_direct'. You need to be aware that "always_direct deny
6774# foo" is NOT the same thing as "never_direct allow foo". You
6775# may need to use a deny rule to exclude a more-specific case of
6776# some other rule. Example:
6777#
6778# acl local-external dstdomain external.foo.net
6779# acl local-servers dstdomain .foo.net
6780# always_direct deny local-external
6781# always_direct allow local-servers
6782#
6783# NOTE: If your goal is to make the client forward the request
6784# directly to the origin server bypassing Squid then this needs
6785# to be done in the client configuration. Squid configuration
6786# can only tell Squid how Squid should fetch the object.
6787#
6788# NOTE: This directive is not related to caching. The replies
6789# is cached as usual even if you use always_direct. To not cache
6790# the replies see the 'cache' directive.
6791#
6792# This clause supports both fast and slow acl types.
6793# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
6794#Default:
6795# Prevent any cache_peer being used for this request.
6796
6797# TAG: never_direct
6798# Usage: never_direct allow|deny [!]aclname ...
6799#
6800# never_direct is the opposite of always_direct. Please read
6801# the description for always_direct if you have not already.
6802#
6803# With 'never_direct' you can use ACL elements to specify
6804# requests which should NEVER be forwarded directly to origin
6805# servers. For example, to force the use of a proxy for all
6806# requests, except those in your local domain use something like:
6807#
6808# acl local-servers dstdomain .foo.net
6809# never_direct deny local-servers
6810# never_direct allow all
6811#
6812# or if Squid is inside a firewall and there are local intranet
6813# servers inside the firewall use something like:
6814#
6815# acl local-intranet dstdomain .foo.net
6816# acl local-external dstdomain external.foo.net
6817# always_direct deny local-external
6818# always_direct allow local-intranet
6819# never_direct allow all
6820#
6821# This clause supports both fast and slow acl types.
6822# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
6823#Default:
6824# Allow DNS results to be used for this request.
6825
6826# ADVANCED NETWORKING OPTIONS
6827# -----------------------------------------------------------------------------
6828
6829# TAG: incoming_udp_average
6830# Heavy voodoo here. I can't even believe you are reading this.
6831# Are you crazy? Don't even think about adjusting these unless
6832# you understand the algorithms in comm_select.c first!
6833#Default:
6834# incoming_udp_average 6
6835
6836# TAG: incoming_tcp_average
6837# Heavy voodoo here. I can't even believe you are reading this.
6838# Are you crazy? Don't even think about adjusting these unless
6839# you understand the algorithms in comm_select.c first!
6840#Default:
6841# incoming_tcp_average 4
6842
6843# TAG: incoming_dns_average
6844# Heavy voodoo here. I can't even believe you are reading this.
6845# Are you crazy? Don't even think about adjusting these unless
6846# you understand the algorithms in comm_select.c first!
6847#Default:
6848# incoming_dns_average 4
6849
6850# TAG: min_udp_poll_cnt
6851# Heavy voodoo here. I can't even believe you are reading this.
6852# Are you crazy? Don't even think about adjusting these unless
6853# you understand the algorithms in comm_select.c first!
6854#Default:
6855# min_udp_poll_cnt 8
6856
6857# TAG: min_dns_poll_cnt
6858# Heavy voodoo here. I can't even believe you are reading this.
6859# Are you crazy? Don't even think about adjusting these unless
6860# you understand the algorithms in comm_select.c first!
6861#Default:
6862# min_dns_poll_cnt 8
6863
6864# TAG: min_tcp_poll_cnt
6865# Heavy voodoo here. I can't even believe you are reading this.
6866# Are you crazy? Don't even think about adjusting these unless
6867# you understand the algorithms in comm_select.c first!
6868#Default:
6869# min_tcp_poll_cnt 8
6870
6871# TAG: accept_filter
6872# FreeBSD:
6873#
6874# The name of an accept(2) filter to install on Squid's
6875# listen socket(s). This feature is perhaps specific to
6876# FreeBSD and requires support in the kernel.
6877#
6878# The 'httpready' filter delays delivering new connections
6879# to Squid until a full HTTP request has been received.
6880# See the accf_http(9) man page for details.
6881#
6882# The 'dataready' filter delays delivering new connections
6883# to Squid until there is some data to process.
6884# See the accf_dataready(9) man page for details.
6885#
6886# Linux:
6887#
6888# The 'data' filter delays delivering of new connections
6889# to Squid until there is some data to process by TCP_ACCEPT_DEFER.
6890# You may optionally specify a number of seconds to wait by
6891# 'data=N' where N is the number of seconds. Defaults to 30
6892# if not specified. See the tcp(7) man page for details.
6893#EXAMPLE:
6894## FreeBSD
6895#accept_filter httpready
6896## Linux
6897#accept_filter data
6898#Default:
6899# none
6900
6901# TAG: client_ip_max_connections
6902# Set an absolute limit on the number of connections a single
6903# client IP can use. Any more than this and Squid will begin to drop
6904# new connections from the client until it closes some links.
6905#
6906# Note that this is a global limit. It affects all HTTP, HTCP, Gopher and FTP
6907# connections from the client. For finer control use the ACL access controls.
6908#
6909# Requires client_db to be enabled (the default).
6910#
6911# WARNING: This may noticably slow down traffic received via external proxies
6912# or NAT devices and cause them to rebound error messages back to their clients.
6913#Default:
6914# No limit.
6915
6916# TAG: tcp_recv_bufsize (bytes)
6917# Size of receive buffer to set for TCP sockets. Probably just
6918# as easy to change your kernel's default.
6919# Omit from squid.conf to use the default buffer size.
6920#Default:
6921# Use operating system TCP defaults.
6922
6923# ICAP OPTIONS
6924# -----------------------------------------------------------------------------
6925
6926# TAG: icap_enable on|off
6927# If you want to enable the ICAP module support, set this to on.
6928#Default:
6929# icap_enable off
6930
6931# TAG: icap_connect_timeout
6932# This parameter specifies how long to wait for the TCP connect to
6933# the requested ICAP server to complete before giving up and either
6934# terminating the HTTP transaction or bypassing the failure.
6935#
6936# The default for optional services is peer_connect_timeout.
6937# The default for essential services is connect_timeout.
6938# If this option is explicitly set, its value applies to all services.
6939#Default:
6940# none
6941
6942# TAG: icap_io_timeout time-units
6943# This parameter specifies how long to wait for an I/O activity on
6944# an established, active ICAP connection before giving up and
6945# either terminating the HTTP transaction or bypassing the
6946# failure.
6947#Default:
6948# Use read_timeout.
6949
6950# TAG: icap_service_failure_limit limit [in memory-depth time-units]
6951# The limit specifies the number of failures that Squid tolerates
6952# when establishing a new TCP connection with an ICAP service. If
6953# the number of failures exceeds the limit, the ICAP service is
6954# not used for new ICAP requests until it is time to refresh its
6955# OPTIONS.
6956#
6957# A negative value disables the limit. Without the limit, an ICAP
6958# service will not be considered down due to connectivity failures
6959# between ICAP OPTIONS requests.
6960#
6961# Squid forgets ICAP service failures older than the specified
6962# value of memory-depth. The memory fading algorithm
6963# is approximate because Squid does not remember individual
6964# errors but groups them instead, splitting the option
6965# value into ten time slots of equal length.
6966#
6967# When memory-depth is 0 and by default this option has no
6968# effect on service failure expiration.
6969#
6970# Squid always forgets failures when updating service settings
6971# using an ICAP OPTIONS transaction, regardless of this option
6972# setting.
6973#
6974# For example,
6975# # suspend service usage after 10 failures in 5 seconds:
6976# icap_service_failure_limit 10 in 5 seconds
6977#Default:
6978# icap_service_failure_limit 10
6979
6980# TAG: icap_service_revival_delay
6981# The delay specifies the number of seconds to wait after an ICAP
6982# OPTIONS request failure before requesting the options again. The
6983# failed ICAP service is considered "down" until fresh OPTIONS are
6984# fetched.
6985#
6986# The actual delay cannot be smaller than the hardcoded minimum
6987# delay of 30 seconds.
6988#Default:
6989# icap_service_revival_delay 180
6990
6991# TAG: icap_preview_enable on|off
6992# The ICAP Preview feature allows the ICAP server to handle the
6993# HTTP message by looking only at the beginning of the message body
6994# or even without receiving the body at all. In some environments,
6995# previews greatly speedup ICAP processing.
6996#
6997# During an ICAP OPTIONS transaction, the server may tell Squid what
6998# HTTP messages should be previewed and how big the preview should be.
6999# Squid will not use Preview if the server did not request one.
7000#
7001# To disable ICAP Preview for all ICAP services, regardless of
7002# individual ICAP server OPTIONS responses, set this option to "off".
7003#Example:
7004#icap_preview_enable off
7005#Default:
7006# icap_preview_enable on
7007
7008# TAG: icap_preview_size
7009# The default size of preview data to be sent to the ICAP server.
7010# This value might be overwritten on a per server basis by OPTIONS requests.
7011#Default:
7012# No preview sent.
7013
7014# TAG: icap_206_enable on|off
7015# 206 (Partial Content) responses is an ICAP extension that allows the
7016# ICAP agents to optionally combine adapted and original HTTP message
7017# content. The decision to combine is postponed until the end of the
7018# ICAP response. Squid supports Partial Content extension by default.
7019#
7020# Activation of the Partial Content extension is negotiated with each
7021# ICAP service during OPTIONS exchange. Most ICAP servers should handle
7022# negotation correctly even if they do not support the extension, but
7023# some might fail. To disable Partial Content support for all ICAP
7024# services and to avoid any negotiation, set this option to "off".
7025#
7026# Example:
7027# icap_206_enable off
7028#Default:
7029# icap_206_enable on
7030
7031# TAG: icap_default_options_ttl
7032# The default TTL value for ICAP OPTIONS responses that don't have
7033# an Options-TTL header.
7034#Default:
7035# icap_default_options_ttl 60
7036
7037# TAG: icap_persistent_connections on|off
7038# Whether or not Squid should use persistent connections to
7039# an ICAP server.
7040#Default:
7041# icap_persistent_connections on
7042
7043# TAG: adaptation_send_client_ip on|off
7044# If enabled, Squid shares HTTP client IP information with adaptation
7045# services. For ICAP, Squid adds the X-Client-IP header to ICAP requests.
7046# For eCAP, Squid sets the libecap::metaClientIp transaction option.
7047#
7048# See also: adaptation_uses_indirect_client
7049#Default:
7050# adaptation_send_client_ip off
7051
7052# TAG: adaptation_send_username on|off
7053# This sends authenticated HTTP client username (if available) to
7054# the adaptation service.
7055#
7056# For ICAP, the username value is encoded based on the
7057# icap_client_username_encode option and is sent using the header
7058# specified by the icap_client_username_header option.
7059#Default:
7060# adaptation_send_username off
7061
7062# TAG: icap_client_username_header
7063# ICAP request header name to use for adaptation_send_username.
7064#Default:
7065# icap_client_username_header X-Client-Username
7066
7067# TAG: icap_client_username_encode on|off
7068# Whether to base64 encode the authenticated client username.
7069#Default:
7070# icap_client_username_encode off
7071
7072# TAG: icap_service
7073# Defines a single ICAP service using the following format:
7074#
7075# icap_service id vectoring_point uri [option ...]
7076#
7077# id: ID
7078# an opaque identifier or name which is used to direct traffic to
7079# this specific service. Must be unique among all adaptation
7080# services in squid.conf.
7081#
7082# vectoring_point: reqmod_precache|reqmod_postcache|respmod_precache|respmod_postcache
7083# This specifies at which point of transaction processing the
7084# ICAP service should be activated. *_postcache vectoring points
7085# are not yet supported.
7086#
7087# uri: icap://servername:port/servicepath
7088# ICAP server and service location.
7089#
7090# ICAP does not allow a single service to handle both REQMOD and RESPMOD
7091# transactions. Squid does not enforce that requirement. You can specify
7092# services with the same service_url and different vectoring_points. You
7093# can even specify multiple identical services as long as their
7094# service_names differ.
7095#
7096# To activate a service, use the adaptation_access directive. To group
7097# services, use adaptation_service_chain and adaptation_service_set.
7098#
7099# Service options are separated by white space. ICAP services support
7100# the following name=value options:
7101#
7102# bypass=on|off|1|0
7103# If set to 'on' or '1', the ICAP service is treated as
7104# optional. If the service cannot be reached or malfunctions,
7105# Squid will try to ignore any errors and process the message as
7106# if the service was not enabled. No all ICAP errors can be
7107# bypassed. If set to 0, the ICAP service is treated as
7108# essential and all ICAP errors will result in an error page
7109# returned to the HTTP client.
7110#
7111# Bypass is off by default: services are treated as essential.
7112#
7113# routing=on|off|1|0
7114# If set to 'on' or '1', the ICAP service is allowed to
7115# dynamically change the current message adaptation plan by
7116# returning a chain of services to be used next. The services
7117# are specified using the X-Next-Services ICAP response header
7118# value, formatted as a comma-separated list of service names.
7119# Each named service should be configured in squid.conf. Other
7120# services are ignored. An empty X-Next-Services value results
7121# in an empty plan which ends the current adaptation.
7122#
7123# Dynamic adaptation plan may cross or cover multiple supported
7124# vectoring points in their natural processing order.
7125#
7126# Routing is not allowed by default: the ICAP X-Next-Services
7127# response header is ignored.
7128#
7129# ipv6=on|off
7130# Only has effect on split-stack systems. The default on those systems
7131# is to use IPv4-only connections. When set to 'on' this option will
7132# make Squid use IPv6-only connections to contact this ICAP service.
7133#
7134# on-overload=block|bypass|wait|force
7135# If the service Max-Connections limit has been reached, do
7136# one of the following for each new ICAP transaction:
7137# * block: send an HTTP error response to the client
7138# * bypass: ignore the "over-connected" ICAP service
7139# * wait: wait (in a FIFO queue) for an ICAP connection slot
7140# * force: proceed, ignoring the Max-Connections limit
7141#
7142# In SMP mode with N workers, each worker assumes the service
7143# connection limit is Max-Connections/N, even though not all
7144# workers may use a given service.
7145#
7146# The default value is "bypass" if service is bypassable,
7147# otherwise it is set to "wait".
7148#
7149#
7150# max-conn=number
7151# Use the given number as the Max-Connections limit, regardless
7152# of the Max-Connections value given by the service, if any.
7153#
7154# Older icap_service format without optional named parameters is
7155# deprecated but supported for backward compatibility.
7156#
7157#Example:
7158#icap_service svcBlocker reqmod_precache icap://icap1.mydomain.net:1344/reqmod bypass=0
7159#icap_service svcLogger reqmod_precache icap://icap2.mydomain.net:1344/respmod routing=on
7160#Default:
7161# none
7162
7163# TAG: icap_class
7164# This deprecated option was documented to define an ICAP service
7165# chain, even though it actually defined a set of similar, redundant
7166# services, and the chains were not supported.
7167#
7168# To define a set of redundant services, please use the
7169# adaptation_service_set directive. For service chains, use
7170# adaptation_service_chain.
7171#Default:
7172# none
7173
7174# TAG: icap_access
7175# This option is deprecated. Please use adaptation_access, which
7176# has the same ICAP functionality, but comes with better
7177# documentation, and eCAP support.
7178#Default:
7179# none
7180
7181# eCAP OPTIONS
7182# -----------------------------------------------------------------------------
7183
7184# TAG: ecap_enable on|off
7185# Controls whether eCAP support is enabled.
7186#Default:
7187# ecap_enable off
7188
7189# TAG: ecap_service
7190# Defines a single eCAP service
7191#
7192# ecap_service id vectoring_point uri [option ...]
7193#
7194# id: ID
7195# an opaque identifier or name which is used to direct traffic to
7196# this specific service. Must be unique among all adaptation
7197# services in squid.conf.
7198#
7199# vectoring_point: reqmod_precache|reqmod_postcache|respmod_precache|respmod_postcache
7200# This specifies at which point of transaction processing the
7201# eCAP service should be activated. *_postcache vectoring points
7202# are not yet supported.
7203#
7204# uri: ecap://vendor/service_name?custom&cgi=style&parameters=optional
7205# Squid uses the eCAP service URI to match this configuration
7206# line with one of the dynamically loaded services. Each loaded
7207# eCAP service must have a unique URI. Obtain the right URI from
7208# the service provider.
7209#
7210# To activate a service, use the adaptation_access directive. To group
7211# services, use adaptation_service_chain and adaptation_service_set.
7212#
7213# Service options are separated by white space. eCAP services support
7214# the following name=value options:
7215#
7216# bypass=on|off|1|0
7217# If set to 'on' or '1', the eCAP service is treated as optional.
7218# If the service cannot be reached or malfunctions, Squid will try
7219# to ignore any errors and process the message as if the service
7220# was not enabled. No all eCAP errors can be bypassed.
7221# If set to 'off' or '0', the eCAP service is treated as essential
7222# and all eCAP errors will result in an error page returned to the
7223# HTTP client.
7224#
7225# Bypass is off by default: services are treated as essential.
7226#
7227# routing=on|off|1|0
7228# If set to 'on' or '1', the eCAP service is allowed to
7229# dynamically change the current message adaptation plan by
7230# returning a chain of services to be used next.
7231#
7232# Dynamic adaptation plan may cross or cover multiple supported
7233# vectoring points in their natural processing order.
7234#
7235# Routing is not allowed by default.
7236#
7237# Older ecap_service format without optional named parameters is
7238# deprecated but supported for backward compatibility.
7239#
7240#
7241#Example:
7242#ecap_service s1 reqmod_precache ecap://filters.R.us/leakDetector?on_error=block bypass=off
7243#ecap_service s2 respmod_precache ecap://filters.R.us/virusFilter config=/etc/vf.cfg bypass=on
7244#Default:
7245# none
7246
7247# TAG: loadable_modules
7248# Instructs Squid to load the specified dynamic module(s) or activate
7249# preloaded module(s).
7250#Example:
7251#loadable_modules /usr/lib/MinimalAdapter.so
7252#Default:
7253# none
7254
7255# MESSAGE ADAPTATION OPTIONS
7256# -----------------------------------------------------------------------------
7257
7258# TAG: adaptation_service_set
7259#
7260# Configures an ordered set of similar, redundant services. This is
7261# useful when hot standby or backup adaptation servers are available.
7262#
7263# adaptation_service_set set_name service_name1 service_name2 ...
7264#
7265# The named services are used in the set declaration order. The first
7266# applicable adaptation service from the set is used first. The next
7267# applicable service is tried if and only if the transaction with the
7268# previous service fails and the message waiting to be adapted is still
7269# intact.
7270#
7271# When adaptation starts, broken services are ignored as if they were
7272# not a part of the set. A broken service is a down optional service.
7273#
7274# The services in a set must be attached to the same vectoring point
7275# (e.g., pre-cache) and use the same adaptation method (e.g., REQMOD).
7276#
7277# If all services in a set are optional then adaptation failures are
7278# bypassable. If all services in the set are essential, then a
7279# transaction failure with one service may still be retried using
7280# another service from the set, but when all services fail, the master
7281# transaction fails as well.
7282#
7283# A set may contain a mix of optional and essential services, but that
7284# is likely to lead to surprising results because broken services become
7285# ignored (see above), making previously bypassable failures fatal.
7286# Technically, it is the bypassability of the last failed service that
7287# matters.
7288#
7289# See also: adaptation_access adaptation_service_chain
7290#
7291#Example:
7292#adaptation_service_set svcBlocker urlFilterPrimary urlFilterBackup
7293#adaptation service_set svcLogger loggerLocal loggerRemote
7294#Default:
7295# none
7296
7297# TAG: adaptation_service_chain
7298#
7299# Configures a list of complementary services that will be applied
7300# one-by-one, forming an adaptation chain or pipeline. This is useful
7301# when Squid must perform different adaptations on the same message.
7302#
7303# adaptation_service_chain chain_name service_name1 svc_name2 ...
7304#
7305# The named services are used in the chain declaration order. The first
7306# applicable adaptation service from the chain is used first. The next
7307# applicable service is applied to the successful adaptation results of
7308# the previous service in the chain.
7309#
7310# When adaptation starts, broken services are ignored as if they were
7311# not a part of the chain. A broken service is a down optional service.
7312#
7313# Request satisfaction terminates the adaptation chain because Squid
7314# does not currently allow declaration of RESPMOD services at the
7315# "reqmod_precache" vectoring point (see icap_service or ecap_service).
7316#
7317# The services in a chain must be attached to the same vectoring point
7318# (e.g., pre-cache) and use the same adaptation method (e.g., REQMOD).
7319#
7320# A chain may contain a mix of optional and essential services. If an
7321# essential adaptation fails (or the failure cannot be bypassed for
7322# other reasons), the master transaction fails. Otherwise, the failure
7323# is bypassed as if the failed adaptation service was not in the chain.
7324#
7325# See also: adaptation_access adaptation_service_set
7326#
7327#Example:
7328#adaptation_service_chain svcRequest requestLogger urlFilter leakDetector
7329#Default:
7330# none
7331
7332# TAG: adaptation_access
7333# Sends an HTTP transaction to an ICAP or eCAP adaptation service.
7334#
7335# adaptation_access service_name allow|deny [!]aclname...
7336# adaptation_access set_name allow|deny [!]aclname...
7337#
7338# At each supported vectoring point, the adaptation_access
7339# statements are processed in the order they appear in this
7340# configuration file. Statements pointing to the following services
7341# are ignored (i.e., skipped without checking their ACL):
7342#
7343# - services serving different vectoring points
7344# - "broken-but-bypassable" services
7345# - "up" services configured to ignore such transactions
7346# (e.g., based on the ICAP Transfer-Ignore header).
7347#
7348# When a set_name is used, all services in the set are checked
7349# using the same rules, to find the first applicable one. See
7350# adaptation_service_set for details.
7351#
7352# If an access list is checked and there is a match, the
7353# processing stops: For an "allow" rule, the corresponding
7354# adaptation service is used for the transaction. For a "deny"
7355# rule, no adaptation service is activated.
7356#
7357# It is currently not possible to apply more than one adaptation
7358# service at the same vectoring point to the same HTTP transaction.
7359#
7360# See also: icap_service and ecap_service
7361#
7362#Example:
7363#adaptation_access service_1 allow all
7364#Default:
7365# Allow, unless rules exist in squid.conf.
7366
7367# TAG: adaptation_service_iteration_limit
7368# Limits the number of iterations allowed when applying adaptation
7369# services to a message. If your longest adaptation set or chain
7370# may have more than 16 services, increase the limit beyond its
7371# default value of 16. If detecting infinite iteration loops sooner
7372# is critical, make the iteration limit match the actual number
7373# of services in your longest adaptation set or chain.
7374#
7375# Infinite adaptation loops are most likely with routing services.
7376#
7377# See also: icap_service routing=1
7378#Default:
7379# adaptation_service_iteration_limit 16
7380
7381# TAG: adaptation_masterx_shared_names
7382# For each master transaction (i.e., the HTTP request and response
7383# sequence, including all related ICAP and eCAP exchanges), Squid
7384# maintains a table of metadata. The table entries are (name, value)
7385# pairs shared among eCAP and ICAP exchanges. The table is destroyed
7386# with the master transaction.
7387#
7388# This option specifies the table entry names that Squid must accept
7389# from and forward to the adaptation transactions.
7390#
7391# An ICAP REQMOD or RESPMOD transaction may set an entry in the
7392# shared table by returning an ICAP header field with a name
7393# specified in adaptation_masterx_shared_names.
7394#
7395# An eCAP REQMOD or RESPMOD transaction may set an entry in the
7396# shared table by implementing the libecap::visitEachOption() API
7397# to provide an option with a name specified in
7398# adaptation_masterx_shared_names.
7399#
7400# Squid will store and forward the set entry to subsequent adaptation
7401# transactions within the same master transaction scope.
7402#
7403# Only one shared entry name is supported at this time.
7404#
7405#Example:
7406## share authentication information among ICAP services
7407#adaptation_masterx_shared_names X-Subscriber-ID
7408#Default:
7409# none
7410
7411# TAG: adaptation_meta
7412# This option allows Squid administrator to add custom ICAP request
7413# headers or eCAP options to Squid ICAP requests or eCAP transactions.
7414# Use it to pass custom authentication tokens and other
7415# transaction-state related meta information to an ICAP/eCAP service.
7416#
7417# The addition of a meta header is ACL-driven:
7418# adaptation_meta name value [!]aclname ...
7419#
7420# Processing for a given header name stops after the first ACL list match.
7421# Thus, it is impossible to add two headers with the same name. If no ACL
7422# lists match for a given header name, no such header is added. For
7423# example:
7424#
7425# # do not debug transactions except for those that need debugging
7426# adaptation_meta X-Debug 1 needs_debugging
7427#
7428# # log all transactions except for those that must remain secret
7429# adaptation_meta X-Log 1 !keep_secret
7430#
7431# # mark transactions from users in the "G 1" group
7432# adaptation_meta X-Authenticated-Groups "G 1" authed_as_G1
7433#
7434# The "value" parameter may be a regular squid.conf token or a "double
7435# quoted string". Within the quoted string, use backslash (\) to escape
7436# any character, which is currently only useful for escaping backslashes
7437# and double quotes. For example,
7438# "this string has one backslash (\\) and two \"quotes\""
7439#
7440# Used adaptation_meta header values may be logged via %note
7441# logformat code. If multiple adaptation_meta headers with the same name
7442# are used during master transaction lifetime, the header values are
7443# logged in the order they were used and duplicate values are ignored
7444# (only the first repeated value will be logged).
7445#Default:
7446# none
7447
7448# TAG: icap_retry
7449# This ACL determines which retriable ICAP transactions are
7450# retried. Transactions that received a complete ICAP response
7451# and did not have to consume or produce HTTP bodies to receive
7452# that response are usually retriable.
7453#
7454# icap_retry allow|deny [!]aclname ...
7455#
7456# Squid automatically retries some ICAP I/O timeouts and errors
7457# due to persistent connection race conditions.
7458#
7459# See also: icap_retry_limit
7460#Default:
7461# icap_retry deny all
7462
7463# TAG: icap_retry_limit
7464# Limits the number of retries allowed.
7465#
7466# Communication errors due to persistent connection race
7467# conditions are unavoidable, automatically retried, and do not
7468# count against this limit.
7469#
7470# See also: icap_retry
7471#Default:
7472# No retries are allowed.
7473
7474# DNS OPTIONS
7475# -----------------------------------------------------------------------------
7476
7477# TAG: check_hostnames
7478# For security and stability reasons Squid can check
7479# hostnames for Internet standard RFC compliance. If you want
7480# Squid to perform these checks turn this directive on.
7481#Default:
7482# check_hostnames off
7483
7484# TAG: allow_underscore
7485# Underscore characters is not strictly allowed in Internet hostnames
7486# but nevertheless used by many sites. Set this to off if you want
7487# Squid to be strict about the standard.
7488# This check is performed only when check_hostnames is set to on.
7489#Default:
7490# allow_underscore on
7491
7492# TAG: dns_retransmit_interval
7493# Initial retransmit interval for DNS queries. The interval is
7494# doubled each time all configured DNS servers have been tried.
7495#Default:
7496# dns_retransmit_interval 5 seconds
7497
7498# TAG: dns_timeout
7499# DNS Query timeout. If no response is received to a DNS query
7500# within this time all DNS servers for the queried domain
7501# are assumed to be unavailable.
7502#Default:
7503# dns_timeout 30 seconds
7504
7505# TAG: dns_packet_max
7506# Maximum number of bytes packet size to advertise via EDNS.
7507# Set to "none" to disable EDNS large packet support.
7508#
7509# For legacy reasons DNS UDP replies will default to 512 bytes which
7510# is too small for many responses. EDNS provides a means for Squid to
7511# negotiate receiving larger responses back immediately without having
7512# to failover with repeat requests. Responses larger than this limit
7513# will retain the old behaviour of failover to TCP DNS.
7514#
7515# Squid has no real fixed limit internally, but allowing packet sizes
7516# over 1500 bytes requires network jumbogram support and is usually not
7517# necessary.
7518#
7519# WARNING: The RFC also indicates that some older resolvers will reply
7520# with failure of the whole request if the extension is added. Some
7521# resolvers have already been identified which will reply with mangled
7522# EDNS response on occasion. Usually in response to many-KB jumbogram
7523# sizes being advertised by Squid.
7524# Squid will currently treat these both as an unable-to-resolve domain
7525# even if it would be resolvable without EDNS.
7526#Default:
7527# EDNS disabled
7528
7529# TAG: dns_defnames on|off
7530# Normally the RES_DEFNAMES resolver option is disabled
7531# (see res_init(3)). This prevents caches in a hierarchy
7532# from interpreting single-component hostnames locally. To allow
7533# Squid to handle single-component names, enable this option.
7534#Default:
7535# Search for single-label domain names is disabled.
7536
7537# TAG: dns_multicast_local on|off
7538# When set to on, Squid sends multicast DNS lookups on the local
7539# network for domains ending in .local and .arpa.
7540# This enables local servers and devices to be contacted in an
7541# ad-hoc or zero-configuration network environment.
7542#Default:
7543# Search for .local and .arpa names is disabled.
7544
7545# TAG: dns_nameservers
7546# Use this if you want to specify a list of DNS name servers
7547# (IP addresses) to use instead of those given in your
7548# /etc/resolv.conf file.
7549#
7550# On Windows platforms, if no value is specified here or in
7551# the /etc/resolv.conf file, the list of DNS name servers are
7552# taken from the Windows registry, both static and dynamic DHCP
7553# configurations are supported.
7554#
7555# Example: dns_nameservers 10.0.0.1 192.172.0.4
7556#Default:
7557# Use operating system definitions
7558
7559# TAG: hosts_file
7560# Location of the host-local IP name-address associations
7561# database. Most Operating Systems have such a file on different
7562# default locations:
7563# - Un*X & Linux: /etc/hosts
7564# - Windows NT/2000: %SystemRoot%\system32\drivers\etc\hosts
7565# (%SystemRoot% value install default is c:\winnt)
7566# - Windows XP/2003: %SystemRoot%\system32\drivers\etc\hosts
7567# (%SystemRoot% value install default is c:\windows)
7568# - Windows 9x/Me: %windir%\hosts
7569# (%windir% value is usually c:\windows)
7570# - Cygwin: /etc/hosts
7571#
7572# The file contains newline-separated definitions, in the
7573# form ip_address_in_dotted_form name [name ...] names are
7574# whitespace-separated. Lines beginning with an hash (#)
7575# character are comments.
7576#
7577# The file is checked at startup and upon configuration.
7578# If set to 'none', it won't be checked.
7579# If append_domain is used, that domain will be added to
7580# domain-local (i.e. not containing any dot character) host
7581# definitions.
7582#Default:
7583# hosts_file /etc/hosts
7584
7585# TAG: append_domain
7586# Appends local domain name to hostnames without any dots in
7587# them. append_domain must begin with a period.
7588#
7589# Be warned there are now Internet names with no dots in
7590# them using only top-domain names, so setting this may
7591# cause some Internet sites to become unavailable.
7592#
7593#Example:
7594# append_domain .yourdomain.com
7595#Default:
7596# Use operating system definitions
7597
7598# TAG: ignore_unknown_nameservers
7599# By default Squid checks that DNS responses are received
7600# from the same IP addresses they are sent to. If they
7601# don't match, Squid ignores the response and writes a warning
7602# message to cache.log. You can allow responses from unknown
7603# nameservers by setting this option to 'off'.
7604#Default:
7605# ignore_unknown_nameservers on
7606
7607# TAG: dns_v4_first
7608# With the IPv6 Internet being as fast or faster than IPv4 Internet
7609# for most networks Squid prefers to contact websites over IPv6.
7610#
7611# This option reverses the order of preference to make Squid contact
7612# dual-stack websites over IPv4 first. Squid will still perform both
7613# IPv6 and IPv4 DNS lookups before connecting.
7614#
7615# WARNING:
7616# This option will restrict the situations under which IPv6
7617# connectivity is used (and tested), potentially hiding network
7618# problems which would otherwise be detected and warned about.
7619#Default:
7620# dns_v4_first off
7621
7622# TAG: ipcache_size (number of entries)
7623# Maximum number of DNS IP cache entries.
7624#Default:
7625# ipcache_size 1024
7626
7627# TAG: ipcache_low (percent)
7628#Default:
7629# ipcache_low 90
7630
7631# TAG: ipcache_high (percent)
7632# The size, low-, and high-water marks for the IP cache.
7633#Default:
7634# ipcache_high 95
7635
7636# TAG: fqdncache_size (number of entries)
7637# Maximum number of FQDN cache entries.
7638#Default:
7639# fqdncache_size 1024
7640
7641# MISCELLANEOUS
7642# -----------------------------------------------------------------------------
7643
7644# TAG: configuration_includes_quoted_values on|off
7645# If set, Squid will recognize each "quoted string" after a configuration
7646# directive as a single parameter. The quotes are stripped before the
7647# parameter value is interpreted or used.
7648# See "Values with spaces, quotes, and other special characters"
7649# section for more details.
7650#Default:
7651# configuration_includes_quoted_values off
7652
7653# TAG: memory_pools on|off
7654# If set, Squid will keep pools of allocated (but unused) memory
7655# available for future use. If memory is a premium on your
7656# system and you believe your malloc library outperforms Squid
7657# routines, disable this.
7658#Default:
7659# memory_pools on
7660
7661# TAG: memory_pools_limit (bytes)
7662# Used only with memory_pools on:
7663# memory_pools_limit 50 MB
7664#
7665# If set to a non-zero value, Squid will keep at most the specified
7666# limit of allocated (but unused) memory in memory pools. All free()
7667# requests that exceed this limit will be handled by your malloc
7668# library. Squid does not pre-allocate any memory, just safe-keeps
7669# objects that otherwise would be free()d. Thus, it is safe to set
7670# memory_pools_limit to a reasonably high value even if your
7671# configuration will use less memory.
7672#
7673# If set to none, Squid will keep all memory it can. That is, there
7674# will be no limit on the total amount of memory used for safe-keeping.
7675#
7676# To disable memory allocation optimization, do not set
7677# memory_pools_limit to 0 or none. Set memory_pools to "off" instead.
7678#
7679# An overhead for maintaining memory pools is not taken into account
7680# when the limit is checked. This overhead is close to four bytes per
7681# object kept. However, pools may actually _save_ memory because of
7682# reduced memory thrashing in your malloc library.
7683#Default:
7684# memory_pools_limit 5 MB
7685
7686# TAG: forwarded_for on|off|transparent|truncate|delete
7687# If set to "on", Squid will append your client's IP address
7688# in the HTTP requests it forwards. By default it looks like:
7689#
7690# X-Forwarded-For: 192.1.2.3
7691#
7692# If set to "off", it will appear as
7693#
7694# X-Forwarded-For: unknown
7695#
7696# If set to "transparent", Squid will not alter the
7697# X-Forwarded-For header in any way.
7698#
7699# If set to "delete", Squid will delete the entire
7700# X-Forwarded-For header.
7701#
7702# If set to "truncate", Squid will remove all existing
7703# X-Forwarded-For entries, and place the client IP as the sole entry.
7704#Default:
7705# forwarded_for on
7706
7707# TAG: cachemgr_passwd
7708# Specify passwords for cachemgr operations.
7709#
7710# Usage: cachemgr_passwd password action action ...
7711#
7712# Some valid actions are (see cache manager menu for a full list):
7713# 5min
7714# 60min
7715# asndb
7716# authenticator
7717# cbdata
7718# client_list
7719# comm_incoming
7720# config *
7721# counters
7722# delay
7723# digest_stats
7724# dns
7725# events
7726# filedescriptors
7727# fqdncache
7728# histograms
7729# http_headers
7730# info
7731# io
7732# ipcache
7733# mem
7734# menu
7735# netdb
7736# non_peers
7737# objects
7738# offline_toggle *
7739# pconn
7740# peer_select
7741# reconfigure *
7742# redirector
7743# refresh
7744# server_list
7745# shutdown *
7746# store_digest
7747# storedir
7748# utilization
7749# via_headers
7750# vm_objects
7751#
7752# * Indicates actions which will not be performed without a
7753# valid password, others can be performed if not listed here.
7754#
7755# To disable an action, set the password to "disable".
7756# To allow performing an action without a password, set the
7757# password to "none".
7758#
7759# Use the keyword "all" to set the same password for all actions.
7760#
7761#Example:
7762# cachemgr_passwd secret shutdown
7763# cachemgr_passwd lesssssssecret info stats/objects
7764# cachemgr_passwd disable all
7765#Default:
7766# No password. Actions which require password are denied.
7767
7768# TAG: client_db on|off
7769# If you want to disable collecting per-client statistics,
7770# turn off client_db here.
7771#Default:
7772# client_db on
7773
7774# TAG: refresh_all_ims on|off
7775# When you enable this option, squid will always check
7776# the origin server for an update when a client sends an
7777# If-Modified-Since request. Many browsers use IMS
7778# requests when the user requests a reload, and this
7779# ensures those clients receive the latest version.
7780#
7781# By default (off), squid may return a Not Modified response
7782# based on the age of the cached version.
7783#Default:
7784# refresh_all_ims off
7785
7786# TAG: reload_into_ims on|off
7787# When you enable this option, client no-cache or ``reload''
7788# requests will be changed to If-Modified-Since requests.
7789# Doing this VIOLATES the HTTP standard. Enabling this
7790# feature could make you liable for problems which it
7791# causes.
7792#
7793# see also refresh_pattern for a more selective approach.
7794#Default:
7795# reload_into_ims off
7796
7797# TAG: connect_retries
7798# This sets the maximum number of connection attempts made for each
7799# TCP connection. The connect_retries attempts must all still
7800# complete within the connection timeout period.
7801#
7802# The default is not to re-try if the first connection attempt fails.
7803# The (not recommended) maximum is 10 tries.
7804#
7805# A warning message will be generated if it is set to a too-high
7806# value and the configured value will be over-ridden.
7807#
7808# Note: These re-tries are in addition to forward_max_tries
7809# which limit how many different addresses may be tried to find
7810# a useful server.
7811#Default:
7812# Do not retry failed connections.
7813
7814# TAG: retry_on_error
7815# If set to ON Squid will automatically retry requests when
7816# receiving an error response with status 403 (Forbidden),
7817# 500 (Internal Error), 501 or 503 (Service not available).
7818# Status 502 and 504 (Gateway errors) are always retried.
7819#
7820# This is mainly useful if you are in a complex cache hierarchy to
7821# work around access control errors.
7822#
7823# NOTE: This retry will attempt to find another working destination.
7824# Which is different from the server which just failed.
7825#Default:
7826# retry_on_error off
7827
7828# TAG: as_whois_server
7829# WHOIS server to query for AS numbers. NOTE: AS numbers are
7830# queried only when Squid starts up, not for every request.
7831#Default:
7832# as_whois_server whois.ra.net
7833
7834# TAG: offline_mode
7835# Enable this option and Squid will never try to validate cached
7836# objects.
7837#Default:
7838# offline_mode off
7839
7840# TAG: uri_whitespace
7841# What to do with requests that have whitespace characters in the
7842# URI. Options:
7843#
7844# strip: The whitespace characters are stripped out of the URL.
7845# This is the behavior recommended by RFC2396 and RFC3986
7846# for tolerant handling of generic URI.
7847# NOTE: This is one difference between generic URI and HTTP URLs.
7848#
7849# deny: The request is denied. The user receives an "Invalid
7850# Request" message.
7851# This is the behaviour recommended by RFC2616 for safe
7852# handling of HTTP request URL.
7853#
7854# allow: The request is allowed and the URI is not changed. The
7855# whitespace characters remain in the URI. Note the
7856# whitespace is passed to redirector processes if they
7857# are in use.
7858# Note this may be considered a violation of RFC2616
7859# request parsing where whitespace is prohibited in the
7860# URL field.
7861#
7862# encode: The request is allowed and the whitespace characters are
7863# encoded according to RFC1738.
7864#
7865# chop: The request is allowed and the URI is chopped at the
7866# first whitespace.
7867#
7868#
7869# NOTE the current Squid implementation of encode and chop violates
7870# RFC2616 by not using a 301 redirect after altering the URL.
7871#Default:
7872# uri_whitespace strip
7873
7874# TAG: chroot
7875# Specifies a directory where Squid should do a chroot() while
7876# initializing. This also causes Squid to fully drop root
7877# privileges after initializing. This means, for example, if you
7878# use a HTTP port less than 1024 and try to reconfigure, you may
7879# get an error saying that Squid can not open the port.
7880#Default:
7881# none
7882
7883# TAG: balance_on_multiple_ip
7884# Modern IP resolvers in squid sort lookup results by preferred access.
7885# By default squid will use these IP in order and only rotates to
7886# the next listed when the most preffered fails.
7887#
7888# Some load balancing servers based on round robin DNS have been
7889# found not to preserve user session state across requests
7890# to different IP addresses.
7891#
7892# Enabling this directive Squid rotates IP's per request.
7893#Default:
7894# balance_on_multiple_ip off
7895
7896# TAG: pipeline_prefetch
7897# HTTP clients may send a pipeline of 1+N requests to Squid using a
7898# single connection, without waiting for Squid to respond to the first
7899# of those requests. This option limits the number of concurrent
7900# requests Squid will try to handle in parallel. If set to N, Squid
7901# will try to receive and process up to 1+N requests on the same
7902# connection concurrently.
7903#
7904# Defaults to 0 (off) for bandwidth management and access logging
7905# reasons.
7906#
7907# NOTE: pipelining requires persistent connections to clients.
7908#
7909# WARNING: pipelining breaks NTLM and Negotiate/Kerberos authentication.
7910#Default:
7911# Do not pre-parse pipelined requests.
7912
7913# TAG: high_response_time_warning (msec)
7914# If the one-minute median response time exceeds this value,
7915# Squid prints a WARNING with debug level 0 to get the
7916# administrators attention. The value is in milliseconds.
7917#Default:
7918# disabled.
7919
7920# TAG: high_page_fault_warning
7921# If the one-minute average page fault rate exceeds this
7922# value, Squid prints a WARNING with debug level 0 to get
7923# the administrators attention. The value is in page faults
7924# per second.
7925#Default:
7926# disabled.
7927
7928# TAG: high_memory_warning
7929# Note: This option is only available if Squid is rebuilt with the
7930# GNU Malloc with mstats()
7931#
7932# If the memory usage (as determined by gnumalloc, if available and used)
7933# exceeds this amount, Squid prints a WARNING with debug level 0 to get
7934# the administrators attention.
7935#Default:
7936# disabled.
7937
7938# TAG: sleep_after_fork (microseconds)
7939# When this is set to a non-zero value, the main Squid process
7940# sleeps the specified number of microseconds after a fork()
7941# system call. This sleep may help the situation where your
7942# system reports fork() failures due to lack of (virtual)
7943# memory. Note, however, if you have a lot of child
7944# processes, these sleep delays will add up and your
7945# Squid will not service requests for some amount of time
7946# until all the child processes have been started.
7947# On Windows value less then 1000 (1 milliseconds) are
7948# rounded to 1000.
7949#Default:
7950# sleep_after_fork 0
7951
7952# TAG: windows_ipaddrchangemonitor on|off
7953# Note: This option is only available if Squid is rebuilt with the
7954# MS Windows
7955#
7956# On Windows Squid by default will monitor IP address changes and will
7957# reconfigure itself after any detected event. This is very useful for
7958# proxies connected to internet with dial-up interfaces.
7959# In some cases (a Proxy server acting as VPN gateway is one) it could be
7960# desiderable to disable this behaviour setting this to 'off'.
7961# Note: after changing this, Squid service must be restarted.
7962#Default:
7963# windows_ipaddrchangemonitor on
7964
7965# TAG: eui_lookup
7966# Whether to lookup the EUI or MAC address of a connected client.
7967#Default:
7968# eui_lookup on
7969
7970# TAG: max_filedescriptors
7971# Reduce the maximum number of filedescriptors supported below
7972# the usual operating system defaults.
7973#
7974# Remove from squid.conf to inherit the current ulimit setting.
7975#
7976# Note: Changing this requires a restart of Squid. Also
7977# not all I/O types supports large values (eg on Windows).
7978#Default:
7979# Use operating system limits set by ulimit.