#!/bin/sh
#karl@webmedianow.com
#version 1.0

PATH=/bin:/usr/bin:/sbin:/usr/sbin
export PATH

usage(){
cat <<-EOE
Usage:  $0 WARNING CRITICAL
        Where WARNING and CRITICAL are the integer only portions of the
        percentage for the level desired.
        (i.e. 85% Warning & 95% Critical should be input only as "85 95".)
EOE
exit 3
}

if [ $# -lt 2 ]; then
usage
fi

WARNLEVEL=$1
CRITLEVEL=$2

# Setup standard Nagios/NRPE return codes
#
UNKNOWN=3  #(orange)
CRITICAL=2 #(red)
WARNING=1  #(yellow)
OK=0       #(green)

MemTotal=$(grep ^MemTotal: /proc/meminfo | awk '{print $2}')
MemFree=$(grep ^MemFree: /proc/meminfo | awk '{print $2}')
MemUsed=$(( $MemTotal - $MemFree ))
Buffers=$(grep ^Buffers: /proc/meminfo | awk '{print $2}')
Cached=$(grep ^Cached: /proc/meminfo | awk '{print $2}')


WARN=$(( $MemTotal * $WARNLEVEL / 100 ))
CRIT=$(( $MemTotal * $CRITLEVEL / 100 ))

EXITVAL=$OK

if [ $MemUsed -gt $WARN ]; then
  EXITVAL=$WARNING
fi

if [ $MemUsed -gt $CRIT ]; then
  EXITVAL=$CRITICAL
fi

case $EXITVAL in
0) STATUS=OK ;;
1) STATUS="WARNING:$WARN" ;;
2) STATUS="CRITICAL:$CRIT" ;;
3) STATUS=UNKNOWN ;;
*) STATUS=ERROR ;;
esac

echo "$STATUS | Total=$MemTotal;;;;Used=$MemUsed;;;;Free=$MemFree;;;;Buffers=$Buffers;;;;Cached=$Cached"

exit $EXITVAL