[Nagiosplug-help] check_icmp seems flapping - followon to RE: make of nagios-plugins-1.4.5 on AIX 4.3 fails

[Ralph.Grothe at itdz-berlin.de]

> The relevant pieces can be gleaned by
> 	$ grep -B1 'pid & 0xffff' check_icmp.c

I was wondering why I didn't know the --before-context switch 
as it seems to be a GNU grep only goody I suppose.
AIX's grep is too dumb, but I found the line nevertheless.

> Attached is the version we use. You should be able to compile
it 
> stand-alone on any sane system with
> 	$ gcc check_icmp.c -o check_icmp -O2
> 

produced just one warning which I assume can be neglected

$ gcc -O2 -o check_icmp check_icmp.c 
check_icmp.c: In function `recvfrom_wto':
check_icmp.c:975: warning: passing arg 6 of `nrecvfrom' from
incompatible pointer type


$ ls -l check_icmp
-rwxr-xr-x   1 nagios   nagios     86628 Dec 01 09:39 check_icmp

though this beggars description to any security concerned
admin...

$ su root -c 'chown root check_icmp && chmod 04555 check_icmp'
root's Password: 
$ ls -l check_icmp
-r-sr-xr-x   1 root     nagios     86628 Dec 01 09:39 check_icmp

$ ./check_icmp -H 127.0.0.1 -p 5
OK - 127.0.0.1: rta 0.155ms, lost
0%|rta=0.155ms;200.000;500.000;0; pl=0%;40;80;; 

>From this unconscientious and very superficial test it seems to
work.

I will place it in $USER1$ and have my nagios implementation
exercise it for a while
to see if the ruddy host state fields disappear one by one and
remain in a sustained green...



> -----Original Message-----
> From: Andreas Ericsson [mailto:ae at op5.se]
> Sent: Thursday, November 30, 2006 5:00 PM
> To: Grothe, Ralph
> Cc: nagiosplug-help at lists.sourceforge.net
> Subject: Re: [Nagiosplug-help] check_icmp seems flapping -
followon to
> RE: make of nagios-plugins-1.4.5 on AIX 4.3 fails
> 
> 
> Ralph.Grothe at itdz-berlin.de wrote:
> >> -----Original Message-----
> >> From: Andreas Ericsson [mailto:ae at op5.se]
> >> Sent: Thursday, November 30, 2006 2:01 PM
> >> To: Grothe, Ralph
> >> Cc: nagiosplug-help at lists.sourceforge.net
> >> Subject: Re: [Nagiosplug-help] check_icmp seems flapping -
> > followon to
> >> RE: make of nagios-plugins-1.4.5 on AIX 4.3 fails
> >>
> >>
> >> Ralph.Grothe at itdz-berlin.de wrote:
> >>> I am still seem to have some serious trouble with my build
of
> > the
> >>> check_icmp plugin.
> >>>
> >>>
> >>> Now I am curiuous whether my compilation of check_icmp is
ok?
> >>>
> >> You'd get this problem if you use an old check_icmp on a
system
> > that 
> >> handles process id's > 65535. In the old version, check_icmp
> > didn't 
> >> recognize valid ICMP responses because the id-field used in
the
> > icmp 
> >> header is only 16 bits wide, so a 32-bit pid doesn't fit in
it.
> > This 
> >> would typically only happen when the pid of check_icmp is
> > larger than 
> >> 65535, which would explain the checks hopping between OK for

> >> a while and 
> >> non-OK for a while. Judging by "mode: 1" above, I'd say your

> >> check_icmp 
> >> is fairly old and needs to be upgraded. What version of the 
> >> plugins are 
> >> you using?
> > 
> > Oh, I thought I downloaded the latest nagios-plugins tarball
> > (viz. 1.4.5),
> > of which I guess check_icmp is part of.
> > Wait, there should be a revision header in the sources,
> > or maybe check_icmp is revealing its age?
> > 
> > $ /opt/sw/nagios/libexec/check_icmp -V
> > 
> > no it's dumb as a grave
> > 
> > $ /opt/sw/nagios/libexec/check_icmp --version
> > /opt/sw/nagios/libexec/check_icmp: illegal option -- -
> > /opt/sw/nagios/libexec/check_icmp: illegal option -- e
> > /opt/sw/nagios/libexec/check_icmp: illegal option -- r
> > /opt/sw/nagios/libexec/check_icmp: illegal option -- s
> > check_icmp: No hosts to check
> > 
> > 
> > Oops, it isn't behaving according to its own help screen.
> > But you are the author, then you should know better ;-)
> > 
> > $ /opt/sw/nagios/libexec/check_icmp -h|head -15
> > Copyright (c) 2005 Andreas Ericsson <ae at op5.se>
> > Copyright (c) 2005-2006 Nagios Plugin Development Team
> >         <nagiosplug-devel at lists.sourceforge.net>
> > 
> > 
> > 
> > Usage: check_icmp [options] [-H] host1 host2 hostn
> > 
> > Options:
> >  -h, --help
> >     Print detailed help screen
> >  -V, --version
> >     Print version information
> >  -H
> >     specify a target
> > 
> > 
> > Luckily we've got the source
> > 
> > 
> > $ grep -i \$ID
> >
/opt/sw/nagios/build/nagios-plugins-1.4.5/plugins-root/check_icmp
> > .c 
> > * $Id: check_icmp.c,v 1.8 2006/10/24 21:54:06 opensides Exp $
> > 
> > 
> > So is this recent enough?
> > 
> 
> Well, that depends, really. If the patches I sent in (way back)
when 
> this problem was first encountered (iirc someone had upgraded
from 
> FreeBSD 4.x to 5.x and ran into this exact problem) were 
> incorporated in 
> the official release, then this should indeed be recent enough.
It's 
> possible they didn't, or that I forgot to send that patch 
> (although it 
> was definitely circulated around the list a time or two) so
that the 
> official and my version might differ.
> 
> Attached is the version we use. You should be able to compile
it 
> stand-alone on any sane system with
> 	$ gcc check_icmp.c -o check_icmp -O2
> 
> or by replacing check_icmp.c in your plugins directory with
this one.
> 
> The relevant pieces can be gleaned by
> 	$ grep -B1 'pid & 0xffff' check_icmp.c
> 
> if anyone's interested.
> 
> Btw, I think this one still doesn't support "--version",
although it 
> pretends to in the help output ;-)
> 
> -- 
> Andreas Ericsson                   andreas.ericsson at op5.se
> OP5 AB                             www.op5.se
> Tel: +46 8-230225                  Fax: +46 8-230231
>