plugins-scripts/check_log.sh

   1 #!/bin/sh
   2 #
   3 # Log file pattern detector plugin for monitoring
   4 # Written by Ethan Galstad (nagios@nagios.org)
   5 # Last Modified: 07-31-1999
   6 #
   7 # Usage: ./check_log <log_file> <old_log_file> <pattern>
   8 #
   9 # Description:
  10 #
  11 # This plugin will scan a log file (specified by the <log_file> option)
  12 # for a specific pattern (specified by the <pattern> option).  Successive
  13 # calls to the plugin script will only report *new* pattern matches in the
  14 # log file, since an copy of the log file from the previous run is saved
  15 # to <old_log_file>.
  16 #
  17 # Output:
  18 #
  19 # On the first run of the plugin, it will return an OK state with a message
  20 # of "Log check data initialized".  On successive runs, it will return an OK
  21 # state if *no* pattern matches have been found in the *difference* between the
  22 # log file and the older copy of the log file.  If the plugin detects any
  23 # pattern matches in the log diff, it will return a CRITICAL state and print
  24 # out a message is the following format: "(x) last_match", where "x" is the
  25 # total number of pattern matches found in the file and "last_match" is the
  26 # last entry in the log file which matches the pattern.
  27 #
  28 # Notes:
  29 #
  30 # If you use this plugin make sure to keep the following in mind:
  31 #
  32 #    1.  The "max_attempts" value for the service should be 1, as this will
  33 #        prevent the monitoring system from retrying the service check (the
  34 #        next time the check is run it will not produce the same results).
  35 #
  36 #    2.  The "notify_recovery" value for the service should be 0, so that the
  37 #        monitoring system does not notify you of "recoveries" for the check.
  38 #        Since pattern matches in the log file will only be reported once and
  39 #        not the next time, there will always be "recoveries" for the service,
  40 #        even though recoveries really don't apply to this type of check.
  41 #
  42 #    3.  You *must* supply a different <old_file_log> for each service that
  43 #        you define to use this plugin script - even if the different services
  44 #        check the same <log_file> for pattern matches.  This is necessary
  45 #        because of the way the script operates.
  46 #
  47 # Examples:
  48 #
  49 # Check for login failures in the syslog...
  50 #
  51 #   check_log /var/log/messages ./check_log.badlogins.old "LOGIN FAILURE"
  52 #
  53 # Check for port scan alerts generated by Psionic's PortSentry software...
  54 #
  55 #   check_log /var/log/message ./check_log.portscan.old "attackalert"
  56 #
  57
  58 # Paths to commands used in this script.  These
  59 # may have to be modified to match your system setup.
  60
  61 PROGNAME=`/bin/basename $0`
  62 PROGPATH=`echo $0 | sed -e 's,[\\/][^\\/][^\\/]*$,,'`
  63 REVISION="@NP_VERSION@"
  64 PATH="@TRUSTED_PATH@"
  65
  66 export PATH
  67
  68 . $PROGPATH/utils.sh
  69
  70 print_usage() {
  71     echo "Usage: $PROGNAME -F logfile -O oldlog -q query"
  72     echo "Usage: $PROGNAME --help"
  73     echo "Usage: $PROGNAME --version"
  74 }
  75
  76 print_help() {
  77     print_revision $PROGNAME $REVISION
  78     echo ""
  79     print_usage
  80     echo ""
  81     echo "Log file pattern detector plugin for monitoring"
  82     echo ""
  83     support
  84 }
  85
  86 # Make sure the correct number of command line
  87 # arguments have been supplied
  88
  89 if [ $# -lt 1 ]; then
  90     print_usage
  91     exit $STATE_UNKNOWN
  92 fi
  93
  94 # Grab the command line arguments
  95
  96 #logfile=$1
  97 #oldlog=$2
  98 #query=$3
  99 exitstatus=$STATE_WARNING #default
 100 while test -n "$1"; do
 101     case "$1" in
 102         --help)
 103             print_help
 104             exit $STATE_OK
 105             ;;
 106         -h)
 107             print_help
 108             exit $STATE_OK
 109             ;;
 110         --version)
 111             print_revision $PROGNAME $REVISION
 112             exit $STATE_OK
 113             ;;
 114         -V)
 115             print_revision $PROGNAME $REVISION
 116             exit $STATE_OK
 117             ;;
 118         --filename)
 119             logfile=$2
 120             shift
 121             ;;
 122         -F)
 123             logfile=$2
 124             shift
 125             ;;
 126         --oldlog)
 127             oldlog=$2
 128             shift
 129             ;;
 130         -O)
 131             oldlog=$2
 132             shift
 133             ;;
 134         --query)
 135             query=$2
 136             shift
 137             ;;
 138         -q)
 139             query=$2
 140             shift
 141             ;;
 142         -x)
 143             exitstatus=$2
 144             shift
 145             ;;
 146         --exitstatus)
 147             exitstatus=$2
 148             shift
 149             ;;
 150         *)
 151             echo "Unknown argument: $1"
 152             print_usage
 153             exit $STATE_UNKNOWN
 154             ;;
 155     esac
 156     shift
 157 done
 158
 159 # If the source log file doesn't exist, exit
 160
 161 if [ ! -e $logfile ]; then
 162     echo "Log check error: Log file $logfile does not exist!"
 163     exit $STATE_UNKNOWN
 164 elif [ ! -r $logfile ] ; then
 165     echo "Log check error: Log file $logfile is not readable!"
 166     exit $STATE_UNKNOWN
 167 fi
 168
 169 # If the old log file doesn't exist, this must be the first time
 170 # we're running this test, so copy the original log file over to
 171 # the old diff file and exit
 172
 173 if [ ! -e $oldlog ]; then
 174     cat $logfile > $oldlog
 175     echo "Log check data initialized..."
 176     exit $STATE_OK
 177 fi
 178
 179 # The old log file exists, so compare it to the original log now
 180
 181 # The temporary file that the script should use while
 182 # processing the log file.
 183 if [ -x /bin/mktemp ]; then
 184     tempdiff=`/bin/mktemp /tmp/check_log.XXXXXXXXXX`
 185 else
 186     tempdiff=`/bin/date '+%H%M%S'`
 187     tempdiff="/tmp/check_log.${tempdiff}"
 188     touch $tempdiff
 189     chmod 600 $tempdiff
 190 fi
 191
 192 diff $logfile $oldlog | grep -v "^>" > $tempdiff
 193
 194 # Count the number of matching log entries we have
 195 count=`grep -c "$query" $tempdiff`
 196
 197 # Get the last matching entry in the diff file
 198 lastentry=`grep "$query" $tempdiff | tail -1`
 199
 200 rm -f $tempdiff
 201 cat $logfile > $oldlog
 202
 203 if [ "$count" = "0" ]; then # no matches, exit with no error
 204     echo "Log check ok - 0 pattern matches found"
 205     exitstatus=$STATE_OK
 206 else # Print total matche count and the last entry we found
 207     echo "($count) $lastentry"
 208     exitstatus=$STATE_CRITICAL
 209 fi
 210
 211 exit $exitstatus