/***************************************************************************** * * Monitoring check_ntp_peer plugin * * License: GPL * Copyright (c) 2006 Sean Finney * Copyright (c) 2006-2024 Monitoring Plugins Development Team * * Description: * * This file contains the check_ntp_peer plugin * * This plugin checks an NTP server independent of any commandline * programs or external libraries. * * Use this plugin to check the health of an NTP server. It supports * checking the offset with the sync peer, the jitter and stratum. This * plugin will not check the clock offset between the local host and NTP * server; please use check_ntp_time for that purpose. * * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . * * *****************************************************************************/ const char *progname = "check_ntp_peer"; const char *copyright = "2006-2024"; const char *email = "devel@monitoring-plugins.org"; #include "common.h" #include "netutils.h" #include "utils.h" static char *server_address = NULL; static int port = 123; static int verbose = 0; static bool quiet = false; static char *owarn = "60"; static char *ocrit = "120"; static bool do_stratum = false; static char *swarn = "-1:16"; static char *scrit = "-1:16"; static bool do_jitter = false; static char *jwarn = "-1:5000"; static char *jcrit = "-1:10000"; static bool do_truechimers = false; static char *twarn = "0:"; static char *tcrit = "0:"; static bool syncsource_found = false; static bool li_alarm = false; static int process_arguments(int /*argc*/, char ** /*argv*/); static thresholds *offset_thresholds = NULL; static thresholds *jitter_thresholds = NULL; static thresholds *stratum_thresholds = NULL; static thresholds *truechimer_thresholds = NULL; static void print_help(void); void print_usage(void); /* max size of control message data */ #define MAX_CM_SIZE 468 /* this structure holds everything in an ntp control message as per rfc1305 */ typedef struct { uint8_t flags; /* byte with leapindicator,vers,mode. see macros */ uint8_t op; /* R,E,M bits and Opcode */ uint16_t seq; /* Packet sequence */ uint16_t status; /* Clock status */ uint16_t assoc; /* Association */ uint16_t offset; /* Similar to TCP sequence # */ uint16_t count; /* # bytes of data */ char data[MAX_CM_SIZE]; /* ASCII data of the request */ /* NB: not necessarily NULL terminated! */ } ntp_control_message; /* this is an association/status-word pair found in control packet responses */ typedef struct { uint16_t assoc; uint16_t status; } ntp_assoc_status_pair; /* bits 1,2 are the leap indicator */ #define LI_MASK 0xc0 #define LI(x) ((x & LI_MASK) >> 6) #define LI_SET(x, y) \ do { \ x |= ((y << 6) & LI_MASK); \ } while (0) /* and these are the values of the leap indicator */ #define LI_NOWARNING 0x00 #define LI_EXTRASEC 0x01 #define LI_MISSINGSEC 0x02 #define LI_ALARM 0x03 /* bits 3,4,5 are the ntp version */ #define VN_MASK 0x38 #define VN(x) ((x & VN_MASK) >> 3) #define VN_SET(x, y) \ do { \ x |= ((y << 3) & VN_MASK); \ } while (0) #define VN_RESERVED 0x02 /* bits 6,7,8 are the ntp mode */ #define MODE_MASK 0x07 #define MODE(x) (x & MODE_MASK) #define MODE_SET(x, y) \ do { \ x |= (y & MODE_MASK); \ } while (0) /* here are some values */ #define MODE_CLIENT 0x03 #define MODE_CONTROLMSG 0x06 /* In control message, bits 8-10 are R,E,M bits */ #define REM_MASK 0xe0 #define REM_RESP 0x80 #define REM_ERROR 0x40 #define REM_MORE 0x20 /* In control message, bits 11 - 15 are opcode */ #define OP_MASK 0x1f #define OP_SET(x, y) \ do { \ x |= (y & OP_MASK); \ } while (0) #define OP_READSTAT 0x01 #define OP_READVAR 0x02 /* In peer status bytes, bits 6,7,8 determine clock selection status */ #define PEER_SEL(x) ((ntohs(x) >> 8) & 0x07) #define PEER_TRUECHIMER 0x02 #define PEER_INCLUDED 0x04 #define PEER_SYNCSOURCE 0x06 /* NTP control message header is 12 bytes, plus any data in the data * field, plus null padding to the nearest 32-bit boundary per rfc. */ #define SIZEOF_NTPCM(m) (12 + ntohs(m.count) + ((ntohs(m.count) % 4) ? 4 - (ntohs(m.count) % 4) : 0)) /* finally, a little helper or two for debugging: */ #define DBG(x) \ do { \ if (verbose > 1) { \ x; \ } \ } while (0); #define PRINTSOCKADDR(x) \ do { \ printf("%u.%u.%u.%u", (x >> 24) & 0xff, (x >> 16) & 0xff, (x >> 8) & 0xff, x & 0xff); \ } while (0); void print_ntp_control_message(const ntp_control_message *p) { printf("control packet contents:\n"); printf("\tflags: 0x%.2x , 0x%.2x\n", p->flags, p->op); printf("\t li=%d (0x%.2x)\n", LI(p->flags), p->flags & LI_MASK); printf("\t vn=%d (0x%.2x)\n", VN(p->flags), p->flags & VN_MASK); printf("\t mode=%d (0x%.2x)\n", MODE(p->flags), p->flags & MODE_MASK); printf("\t response=%d (0x%.2x)\n", (p->op & REM_RESP) > 0, p->op & REM_RESP); printf("\t more=%d (0x%.2x)\n", (p->op & REM_MORE) > 0, p->op & REM_MORE); printf("\t error=%d (0x%.2x)\n", (p->op & REM_ERROR) > 0, p->op & REM_ERROR); printf("\t op=%d (0x%.2x)\n", p->op & OP_MASK, p->op & OP_MASK); printf("\tsequence: %d (0x%.2x)\n", ntohs(p->seq), ntohs(p->seq)); printf("\tstatus: %d (0x%.2x)\n", ntohs(p->status), ntohs(p->status)); printf("\tassoc: %d (0x%.2x)\n", ntohs(p->assoc), ntohs(p->assoc)); printf("\toffset: %d (0x%.2x)\n", ntohs(p->offset), ntohs(p->offset)); printf("\tcount: %d (0x%.2x)\n", ntohs(p->count), ntohs(p->count)); int numpeers = ntohs(p->count) / (sizeof(ntp_assoc_status_pair)); if (p->op & REM_RESP && p->op & OP_READSTAT) { const ntp_assoc_status_pair *peer = (ntp_assoc_status_pair *)p->data; for (int i = 0; i < numpeers; i++) { printf("\tpeer id %.2x status %.2x", ntohs(peer[i].assoc), ntohs(peer[i].status)); if (PEER_SEL(peer[i].status) >= PEER_SYNCSOURCE) { printf(" <-- current sync source"); } else if (PEER_SEL(peer[i].status) >= PEER_INCLUDED) { printf(" <-- current sync candidate"); } else if (PEER_SEL(peer[i].status) >= PEER_TRUECHIMER) { printf(" <-- outlyer, but truechimer"); } printf("\n"); } } } void setup_control_request(ntp_control_message *p, uint8_t opcode, uint16_t seq) { memset(p, 0, sizeof(ntp_control_message)); LI_SET(p->flags, LI_NOWARNING); VN_SET(p->flags, VN_RESERVED); MODE_SET(p->flags, MODE_CONTROLMSG); OP_SET(p->op, opcode); p->seq = htons(seq); /* Remaining fields are zero for requests */ } /* This function does all the actual work; roughly here's what it does * beside setting the offset, jitter and stratum passed as argument: * - offset can be negative, so if it cannot get the offset, offset_result * is set to UNKNOWN, otherwise OK. * - jitter and stratum are set to -1 if they cannot be retrieved so any * positive value means a success retrieving the value. * - status is set to WARNING if there's no sync.peer (otherwise OK) and is * the return value of the function. * status is pretty much useless as syncsource_found is a global variable * used later in main to check is the server was synchronized. It works * so I left it alone */ int ntp_request(double *offset, int *offset_result, double *jitter, int *stratum, int *num_truechimers) { *offset_result = STATE_UNKNOWN; *jitter = *stratum = -1; *num_truechimers = 0; /* Long-winded explanation: * Getting the sync peer offset, jitter and stratum requires a number of * steps: * 1) Send a READSTAT request. * 2) Interpret the READSTAT reply * a) The data section contains a list of peer identifiers (16 bits) * and associated status words (16 bits) * b) We want the value of 0x06 in the SEL (peer selection) value, * which means "current synchronizatin source". If that's missing, * we take anything better than 0x04 (see the rfc for details) but * set a minimum of warning. * 3) Send a READVAR request for information on each peer identified * in 2b greater than the minimum selection value. * 4) Extract the offset, jitter and stratum value from the data[] * (it's ASCII) */ int min_peer_sel = PEER_INCLUDED; int num_candidates = 0; void *tmp; ntp_assoc_status_pair *peers = NULL; int peer_offset = 0; int peers_size = 0; int npeers = 0; int conn = -1; my_udp_connect(server_address, port, &conn); /* keep sending requests until the server stops setting the * REM_MORE bit, though usually this is only 1 packet. */ ntp_control_message req; do { setup_control_request(&req, OP_READSTAT, 1); DBG(printf("sending READSTAT request")); write(conn, &req, SIZEOF_NTPCM(req)); DBG(print_ntp_control_message(&req)); do { /* Attempt to read the largest size packet possible */ req.count = htons(MAX_CM_SIZE); DBG(printf("receiving READSTAT response")) if (read(conn, &req, SIZEOF_NTPCM(req)) == -1) die(STATE_CRITICAL, "NTP CRITICAL: No response from NTP server\n"); DBG(print_ntp_control_message(&req)); /* discard obviously invalid packets */ if (ntohs(req.count) > MAX_CM_SIZE) die(STATE_CRITICAL, "NTP CRITICAL: Invalid packet received from NTP server\n"); } while (!(req.op & OP_READSTAT && ntohs(req.seq) == 1)); if (LI(req.flags) == LI_ALARM) li_alarm = true; /* Each peer identifier is 4 bytes in the data section, which * we represent as a ntp_assoc_status_pair datatype. */ peers_size += ntohs(req.count); if ((tmp = realloc(peers, peers_size)) == NULL) free(peers), die(STATE_UNKNOWN, "can not (re)allocate 'peers' buffer\n"); peers = tmp; memcpy((void *)((ptrdiff_t)peers + peer_offset), (void *)req.data, ntohs(req.count)); npeers = peers_size / sizeof(ntp_assoc_status_pair); peer_offset += ntohs(req.count); } while (req.op & REM_MORE); /* first, let's find out if we have a sync source, or if there are * at least some candidates. In the latter case we'll issue * a warning but go ahead with the check on them. */ for (int i = 0; i < npeers; i++) { if (PEER_SEL(peers[i].status) >= PEER_TRUECHIMER) { (*num_truechimers)++; if (PEER_SEL(peers[i].status) >= PEER_INCLUDED) { num_candidates++; if (PEER_SEL(peers[i].status) >= PEER_SYNCSOURCE) { syncsource_found = true; min_peer_sel = PEER_SYNCSOURCE; } } } } if (verbose) printf("%d candidate peers available\n", num_candidates); if (verbose && syncsource_found) printf("synchronization source found\n"); int status = STATE_OK; if (!syncsource_found) { status = STATE_WARNING; if (verbose) printf("warning: no synchronization source found\n"); } if (li_alarm) { status = STATE_WARNING; if (verbose) printf("warning: LI_ALARM bit is set\n"); } const char *getvar = "stratum,offset,jitter"; char *data; for (int i = 0; i < npeers; i++) { /* Only query this server if it is the current sync source */ /* If there's no sync.peer, query all candidates and use the best one */ if (PEER_SEL(peers[i].status) >= min_peer_sel) { if (verbose) printf("Getting offset, jitter and stratum for peer %.2x\n", ntohs(peers[i].assoc)); xasprintf(&data, ""); do { setup_control_request(&req, OP_READVAR, 2); req.assoc = peers[i].assoc; /* Putting the wanted variable names in the request * cause the server to provide _only_ the requested values. * thus reducing net traffic, guaranteeing us only a single * datagram in reply, and making interpretation much simpler */ /* Older servers doesn't know what jitter is, so if we get an * error on the first pass we redo it with "dispersion" */ strncpy(req.data, getvar, MAX_CM_SIZE - 1); req.count = htons(strlen(getvar)); DBG(printf("sending READVAR request...\n")); write(conn, &req, SIZEOF_NTPCM(req)); DBG(print_ntp_control_message(&req)); do { req.count = htons(MAX_CM_SIZE); DBG(printf("receiving READVAR response...\n")); read(conn, &req, SIZEOF_NTPCM(req)); DBG(print_ntp_control_message(&req)); } while (!(req.op & OP_READVAR && ntohs(req.seq) == 2)); if (!(req.op & REM_ERROR)) xasprintf(&data, "%s%s", data, req.data); } while (req.op & REM_MORE); if (req.op & REM_ERROR) { if (strstr(getvar, "jitter")) { if (verbose) printf("The command failed. This is usually caused by servers refusing the 'jitter'\nvariable. Restarting with " "'dispersion'...\n"); getvar = "stratum,offset,dispersion"; i--; continue; } if (strlen(getvar)) { if (verbose) printf("Server didn't like dispersion either; will retrieve everything\n"); getvar = ""; i--; continue; } } if (verbose > 1) printf("Server responded: >>>%s<<<\n", data); double tmp_offset = 0; char *value; char *nptr; /* get the offset */ if (verbose) printf("parsing offset from peer %.2x: ", ntohs(peers[i].assoc)); value = np_extract_ntpvar(data, "offset"); nptr = NULL; /* Convert the value if we have one */ if (value != NULL) tmp_offset = strtod(value, &nptr) / 1000; /* If value is null or no conversion was performed */ if (value == NULL || value == nptr) { if (verbose) printf("error: unable to read server offset response.\n"); } else { if (verbose) printf("%.10g\n", tmp_offset); if (*offset_result == STATE_UNKNOWN || fabs(tmp_offset) < fabs(*offset)) { *offset = tmp_offset; *offset_result = STATE_OK; } else { /* Skip this one; move to the next */ continue; } } if (do_jitter) { /* get the jitter */ if (verbose) { printf("parsing %s from peer %.2x: ", strstr(getvar, "dispersion") != NULL ? "dispersion" : "jitter", ntohs(peers[i].assoc)); } value = np_extract_ntpvar(data, strstr(getvar, "dispersion") != NULL ? "dispersion" : "jitter"); nptr = NULL; /* Convert the value if we have one */ if (value != NULL) *jitter = strtod(value, &nptr); /* If value is null or no conversion was performed */ if (value == NULL || value == nptr) { if (verbose) printf("error: unable to read server jitter/dispersion response.\n"); *jitter = -1; } else if (verbose) { printf("%.10g\n", *jitter); } } if (do_stratum) { /* get the stratum */ if (verbose) { printf("parsing stratum from peer %.2x: ", ntohs(peers[i].assoc)); } value = np_extract_ntpvar(data, "stratum"); nptr = NULL; /* Convert the value if we have one */ if (value != NULL) *stratum = strtol(value, &nptr, 10); if (value == NULL || value == nptr) { if (verbose) printf("error: unable to read server stratum response.\n"); *stratum = -1; } else { if (verbose) printf("%i\n", *stratum); } } } /* if (PEER_SEL(peers[i].status) >= min_peer_sel) */ } /* for (i = 0; i < npeers; i++) */ close(conn); if (peers != NULL) free(peers); return status; } int process_arguments(int argc, char **argv) { static struct option longopts[] = { {"version", no_argument, 0, 'V'}, {"help", no_argument, 0, 'h'}, {"verbose", no_argument, 0, 'v'}, {"use-ipv4", no_argument, 0, '4'}, {"use-ipv6", no_argument, 0, '6'}, {"quiet", no_argument, 0, 'q'}, {"warning", required_argument, 0, 'w'}, {"critical", required_argument, 0, 'c'}, {"swarn", required_argument, 0, 'W'}, {"scrit", required_argument, 0, 'C'}, {"jwarn", required_argument, 0, 'j'}, {"jcrit", required_argument, 0, 'k'}, {"twarn", required_argument, 0, 'm'}, {"tcrit", required_argument, 0, 'n'}, {"timeout", required_argument, 0, 't'}, {"hostname", required_argument, 0, 'H'}, {"port", required_argument, 0, 'p'}, {0, 0, 0, 0}}; if (argc < 2) usage("\n"); while (true) { int option = 0; int option_char = getopt_long(argc, argv, "Vhv46qw:c:W:C:j:k:m:n:t:H:p:", longopts, &option); if (option_char == -1 || option_char == EOF || option_char == 1) break; switch (option_char) { case 'h': print_help(); exit(STATE_UNKNOWN); break; case 'V': print_revision(progname, NP_VERSION); exit(STATE_UNKNOWN); break; case 'v': verbose++; break; case 'q': quiet = true; break; case 'w': owarn = optarg; break; case 'c': ocrit = optarg; break; case 'W': do_stratum = true; swarn = optarg; break; case 'C': do_stratum = true; scrit = optarg; break; case 'j': do_jitter = true; jwarn = optarg; break; case 'k': do_jitter = true; jcrit = optarg; break; case 'm': do_truechimers = true; twarn = optarg; break; case 'n': do_truechimers = true; tcrit = optarg; break; case 'H': if (!is_host(optarg)) usage2(_("Invalid hostname/address"), optarg); server_address = strdup(optarg); break; case 'p': port = atoi(optarg); break; case 't': socket_timeout = atoi(optarg); break; case '4': address_family = AF_INET; break; case '6': #ifdef USE_IPV6 address_family = AF_INET6; #else usage4(_("IPv6 support not available")); #endif break; case '?': /* print short usage statement if args not parsable */ usage5(); break; } } if (server_address == NULL) { usage4(_("Hostname was not supplied")); } return 0; } char *perfd_offset(double offset) { return fperfdata("offset", offset, "s", true, offset_thresholds->warning->end, true, offset_thresholds->critical->end, false, 0, false, 0); } char *perfd_jitter(double jitter) { return fperfdata("jitter", jitter, "", do_jitter, jitter_thresholds->warning->end, do_jitter, jitter_thresholds->critical->end, true, 0, false, 0); } char *perfd_stratum(int stratum) { return perfdata("stratum", stratum, "", do_stratum, (int)stratum_thresholds->warning->end, do_stratum, (int)stratum_thresholds->critical->end, true, 0, true, 16); } char *perfd_truechimers(int num_truechimers) { return perfdata("truechimers", num_truechimers, "", do_truechimers, (int)truechimer_thresholds->warning->end, do_truechimers, (int)truechimer_thresholds->critical->end, true, 0, false, 0); } int main(int argc, char *argv[]) { setlocale(LC_ALL, ""); bindtextdomain(PACKAGE, LOCALEDIR); textdomain(PACKAGE); /* Parse extra opts if any */ argv = np_extra_opts(&argc, argv, progname); if (process_arguments(argc, argv) == ERROR) usage4(_("Could not parse arguments")); set_thresholds(&offset_thresholds, owarn, ocrit); set_thresholds(&jitter_thresholds, jwarn, jcrit); set_thresholds(&stratum_thresholds, swarn, scrit); set_thresholds(&truechimer_thresholds, twarn, tcrit); /* initialize alarm signal handling */ signal(SIGALRM, socket_timeout_alarm_handler); /* set socket timeout */ alarm(socket_timeout); int offset_result; int stratum; int num_truechimers; double offset = 0; double jitter = 0; /* This returns either OK or WARNING (See comment preceding ntp_request) */ int result = ntp_request(&offset, &offset_result, &jitter, &stratum, &num_truechimers); if (offset_result == STATE_UNKNOWN) { /* if there's no sync peer (this overrides ntp_request output): */ result = (quiet ? STATE_UNKNOWN : STATE_CRITICAL); } else { /* Be quiet if there's no candidates either */ if (quiet && result == STATE_WARNING) result = STATE_UNKNOWN; result = max_state_alt(result, get_status(fabs(offset), offset_thresholds)); } int oresult = result; int tresult = STATE_UNKNOWN; if (do_truechimers) { tresult = get_status(num_truechimers, truechimer_thresholds); result = max_state_alt(result, tresult); } int sresult = STATE_UNKNOWN; if (do_stratum) { sresult = get_status(stratum, stratum_thresholds); result = max_state_alt(result, sresult); } int jresult = STATE_UNKNOWN; if (do_jitter) { jresult = get_status(jitter, jitter_thresholds); result = max_state_alt(result, jresult); } char *result_line; switch (result) { case STATE_CRITICAL: xasprintf(&result_line, _("NTP CRITICAL:")); break; case STATE_WARNING: xasprintf(&result_line, _("NTP WARNING:")); break; case STATE_OK: xasprintf(&result_line, _("NTP OK:")); break; default: xasprintf(&result_line, _("NTP UNKNOWN:")); break; } if (!syncsource_found) xasprintf(&result_line, "%s %s,", result_line, _("Server not synchronized")); else if (li_alarm) xasprintf(&result_line, "%s %s,", result_line, _("Server has the LI_ALARM bit set")); char *perfdata_line; if (offset_result == STATE_UNKNOWN) { xasprintf(&result_line, "%s %s", result_line, _("Offset unknown")); xasprintf(&perfdata_line, ""); } else if (oresult == STATE_WARNING) { xasprintf(&result_line, "%s %s %.10g secs (WARNING)", result_line, _("Offset"), offset); } else if (oresult == STATE_CRITICAL) { xasprintf(&result_line, "%s %s %.10g secs (CRITICAL)", result_line, _("Offset"), offset); } else { xasprintf(&result_line, "%s %s %.10g secs", result_line, _("Offset"), offset); } xasprintf(&perfdata_line, "%s", perfd_offset(offset)); if (do_jitter) { if (jresult == STATE_WARNING) { xasprintf(&result_line, "%s, jitter=%f (WARNING)", result_line, jitter); } else if (jresult == STATE_CRITICAL) { xasprintf(&result_line, "%s, jitter=%f (CRITICAL)", result_line, jitter); } else { xasprintf(&result_line, "%s, jitter=%f", result_line, jitter); } xasprintf(&perfdata_line, "%s %s", perfdata_line, perfd_jitter(jitter)); } if (do_stratum) { if (sresult == STATE_WARNING) { xasprintf(&result_line, "%s, stratum=%i (WARNING)", result_line, stratum); } else if (sresult == STATE_CRITICAL) { xasprintf(&result_line, "%s, stratum=%i (CRITICAL)", result_line, stratum); } else { xasprintf(&result_line, "%s, stratum=%i", result_line, stratum); } xasprintf(&perfdata_line, "%s %s", perfdata_line, perfd_stratum(stratum)); } if (do_truechimers) { if (tresult == STATE_WARNING) { xasprintf(&result_line, "%s, truechimers=%i (WARNING)", result_line, num_truechimers); } else if (tresult == STATE_CRITICAL) { xasprintf(&result_line, "%s, truechimers=%i (CRITICAL)", result_line, num_truechimers); } else { xasprintf(&result_line, "%s, truechimers=%i", result_line, num_truechimers); } xasprintf(&perfdata_line, "%s %s", perfdata_line, perfd_truechimers(num_truechimers)); } printf("%s|%s\n", result_line, perfdata_line); if (server_address != NULL) free(server_address); return result; } void print_help(void) { print_revision(progname, NP_VERSION); printf("Copyright (c) 2006 Sean Finney\n"); printf(COPYRIGHT, copyright, email); printf("%s\n", _("This plugin checks the selected ntp server")); printf("\n\n"); print_usage(); printf(UT_HELP_VRSN); printf(UT_EXTRA_OPTS); printf(UT_IPv46); printf(UT_HOST_PORT, 'p', "123"); printf(" %s\n", "-q, --quiet"); printf(" %s\n", _("Returns UNKNOWN instead of CRITICAL or WARNING if server isn't synchronized")); printf(" %s\n", "-w, --warning=THRESHOLD"); printf(" %s\n", _("Offset to result in warning status (seconds)")); printf(" %s\n", "-c, --critical=THRESHOLD"); printf(" %s\n", _("Offset to result in critical status (seconds)")); printf(" %s\n", "-W, --swarn=THRESHOLD"); printf(" %s\n", _("Warning threshold for stratum of server's synchronization peer")); printf(" %s\n", "-C, --scrit=THRESHOLD"); printf(" %s\n", _("Critical threshold for stratum of server's synchronization peer")); printf(" %s\n", "-j, --jwarn=THRESHOLD"); printf(" %s\n", _("Warning threshold for jitter")); printf(" %s\n", "-k, --jcrit=THRESHOLD"); printf(" %s\n", _("Critical threshold for jitter")); printf(" %s\n", "-m, --twarn=THRESHOLD"); printf(" %s\n", _("Warning threshold for number of usable time sources (\"truechimers\")")); printf(" %s\n", "-n, --tcrit=THRESHOLD"); printf(" %s\n", _("Critical threshold for number of usable time sources (\"truechimers\")")); printf(UT_CONN_TIMEOUT, DEFAULT_SOCKET_TIMEOUT); printf(UT_VERBOSE); printf("\n"); printf("%s\n", _("This plugin checks an NTP server independent of any commandline")); printf("%s\n\n", _("programs or external libraries.")); printf("%s\n", _("Notes:")); printf(" %s\n", _("Use this plugin to check the health of an NTP server. It supports")); printf(" %s\n", _("checking the offset with the sync peer, the jitter and stratum. This")); printf(" %s\n", _("plugin will not check the clock offset between the local host and NTP")); printf(" %s\n", _("server; please use check_ntp_time for that purpose.")); printf("\n"); printf(UT_THRESHOLDS_NOTES); printf("\n"); printf("%s\n", _("Examples:")); printf(" %s\n", _("Simple NTP server check:")); printf(" %s\n", ("./check_ntp_peer -H ntpserv -w 0.5 -c 1")); printf("\n"); printf(" %s\n", _("Check jitter too, avoiding critical notifications if jitter isn't available")); printf(" %s\n", _("(See Notes above for more details on thresholds formats):")); printf(" %s\n", ("./check_ntp_peer -H ntpserv -w 0.5 -c 1 -j -1:100 -k -1:200")); printf("\n"); printf(" %s\n", _("Only check the number of usable time sources (\"truechimers\"):")); printf(" %s\n", ("./check_ntp_peer -H ntpserv -m @5 -n @3")); printf("\n"); printf(" %s\n", _("Check only stratum:")); printf(" %s\n", ("./check_ntp_peer -H ntpserv -W 4 -C 6")); printf(UT_SUPPORT); } void print_usage(void) { printf("%s\n", _("Usage:")); printf(" %s -H [-4|-6] [-w ] [-c ] [-W ] [-C ]\n", progname); printf(" [-j ] [-k ] [-v verbose]\n"); }