Nagios Custom Plugin: Syslog Directory Increment Check

by wxrdaniel

So at my job, I need a generic script for Nagios to help me make sure the syslog from other servers are coming in.

After some research and banging my head because I haven't code bash script for years, here is my solution:

#!/bin/bash

# Default Check Path
DEFAULT_PATH=/var/log/syslogs/

if [ -z "$1" ]; then
    CHECK_PATH=$DEFAULT_PATH
else
    CHECK_PATH=$1
fi

LOG_FILE=$CHECK_PATH'.LOG_SIZE'

# Set Directory size and logged size
dirSIZE=$(du -s $CHECK_PATH | cut -d'/' -f1)
logSIZE=$(tail -1 $LOG_FILE | cut -d' ' -f2)

# Set timestamp var.
CT=$(date +%s)
LT=$(tail -1 $LOG_FILE | cut -d':' -f1)
TD=$(($CT - $LT | bc))

if [ "$dirSIZE" -eq "$logSIZE" ]; then
    if [ $(($TD / 60)) -lt 10 ]; then
        echo "OK - No change for $(($TD / 60)) minutes"
        exit 0
    elif [ $(($TD / 60)) -le 15 ]; then
        echo "WARNING - No change for $(($TD / 60)) minutes"
        exit 1
    else
        echo "CRITICAL - No change for $(($TD / 60)) minutes"
        exit 2
    fi
elif [ "$dirSIZE" -ne "$logSIZE" ]; then
    echo "OK - $CHECK_PATH: $dirSIZE"
    echo "$CT: $dirSIZE" > $CHECK_PATH.LOG_SIZE
    exit 0
else
    echo "UNKOWN - $0 failed"
    exit 4
fi

Reference: How To Create Nagios Plugins With Bash On Ubuntu 12.10