nagios_check_mem.sh

#!/bin/bash
# slightly modified code from https://exchange.nagios.org/directory/Plugins/System-Metrics/Memory/Check-mem-%28by-Nestor%40Toronto%29/details

if [ "$1" = "-w" ] && [ "$2" -gt "0" ] && [ "$3" = "-c" ] && [ "$4" -gt "0" ]; then
FreeM=`free -m`

memTotal_m=`echo "$FreeM" |grep Mem |awk '{print $2}'`
memUsed_m=`echo "$FreeM" |grep Mem |awk '{print $3}'`
memFree_m=`echo "$FreeM" |grep Mem |awk '{print $4}'`
memBuffer_cache_m=`echo "$FreeM" |grep Mem |awk '{print $6}'`
memAvailable_m=`echo "$FreeM" |grep Mem |awk '{print $7}'`
memUsed_m=$(($memTotal_m-$memFree_m-$memBuffer_cache_m))
memUsedPrc=`echo $((($memUsed_m*100)/$memTotal_m))||cut -d. -f1`


if [ "$memUsedPrc" -ge "$4" ]; then
     echo "Memory: CRITICAL Total: $memTotal_m MB - Used: $memUsed_m MB - $memUsedPrc% used!|
TOTAL=$memTotal_m;;;; USED=$memUsed_m;;;; BUFFER/CACHE=$memBuffer_cache_m;;;; AVAILABLE=$memA
vailable_m;;;;"
     exit 2;
  elif [ "$memUsedPrc" -ge "$2" ]; then
     echo "Memory: WARNING Total: $memTotal_m MB - Used: $memUsed_m MB - $memUsedPrc% used!|T
OTAL=$memTotal_m;;;; USED=$memUsed_m;;;; BUFFER/CACHE=$memBuffer_cache_m;;;; AVAILABLE=$memAv
ailable_m;;;;"
     exit 1;
else
     echo "Memory: OK Total: $memTotal_m MB - Used: $memUsed_m MB - $memUsedPrc% used|TOTAL=$
memTotal_m;;;; USED=$memUsed_m;;;; BUFFER/CACHE=$memBuffer_cache_m;;;; AVAILABLE=$memAvailabl
e_m;;;;"
     exit 0;
fi

else # If inputs are not as expected, print help. 
sName="`echo $0|awk -F '/' '{print $NF}'`"
echo -e "\n\n\t\t### $sName Version 2.1###\n"
echo -e "# Usage:\t$sName -w -c "
echo -e "\t\t= warnlevel and critlevel is percentage value without %\n"
echo "# EXAMPLE:\t/usr/lib64/nagios/plugins/$sName -w 80 -c 90"
echo -e "\nCopyright (C) 2012 Lukasz Gogolin (lukasz.gogolin@gmail.com), improved by Nestor 2
015\n\n"
exit
fi