pfsense-nagios-checks/check_pf_cpu

#!/bin/sh

if [ "$1" = "-w" ] && [ "$2" -gt "0" ] && [ "$3" = "-c" ] && [ "$4" -gt "0" ] ; then
        warn=$2
        crit=$4
        IDLE=$(top -b -d2 | grep 'CPU:' | cut -d',' -f5 | cut -d'%' -f1 | cut -d'.' -f1 | sed -e 's/^[ \t]*//' | tail -1)||exit 3
        #UTIL=`echo "100-$IDLE"| bc`
        UTIL=`expr 100 - $IDLE`
        #UTIL_RND=`echo "100-$IDLE"| bc | awk '{printf("%d\n",$1 + 0.5)}'`
        #echo "DEBUG:   IDLE:$IDLE"
        #echo "DEBUG:   UTIL:$UTIL"
        #echo "DEBUG:   UTIL_RND:$UTIL_RND"
        if [ $UTIL -ge $warn ];then
                if [ $UTIL -ge $crit ]; then
                echo "CRITICAL - CPU Usage = $UTIL%|CPU=$UTIL;;;;"
                exit 2
        else
                echo "WARNING - CPU Usage = $UTIL%|CPU=$UTIL;;;;"
                exit 1
        fi
else
                echo "OK - CPU Usage = $UTIL%|CPU=$UTIL;;;;"
        exit 0
fi

else
        echo "check_cpu.sh - Nagios Plugin for checking CPU idle percentage "
        echo ""
        echo "Usage:    check_pf_cpu.sh -w <warnlevel> -c <critlevel>"
        exit 3
fi