check_yum

#!/bin/bash

# Written by Onno Zweers

# Nagios return codes
STATE_OK=0
STATE_WARNING=1
STATE_CRITICAL=2
STATE_UNKNOWN=3
STATE_DEPENDENT=4

YUM_OUTPUT=`yum check-update 2>&1`
RESULT=$?

EXTRA_INFORMATION="Yum exit code: $RESULT"

# Yum check unsuccessful?
if [ "$RESULT" = "1" ] ; then
    echo "UNKNOWN - error while doing 'yum check-update'. | $EXTRA_INFORMATION"
    echo "Yum output: $YUM_OUTPUT"
    exit $STATE_UNKNOWN
fi

LIST=`echo "$YUM_OUTPUT" | awk '/^$/ {emptylinereached=1;next}; emptylinereached==1 {print}' | egrep '^\w.*\.(x86_64|i.86|noarch)\s' | sed -e 's/\(\w*\)\.\(x86_64\|i.86\|noarch\) .*/\1/'`

COUNT=`echo "$LIST" | wc -l`
if echo "$LIST" | grep --silent '^kernel' ; then
  KERNEL=", including a kernel" 
fi

if [ "$RESULT" = "0" ] ; then
    echo "OK - no yum updates found."
    exit $STATE_OK
else
    LIST=`echo $LIST | tr '\n' ' '`
    if [ "$1" == "--only-warn" ] ; then
        echo "WARNING - $COUNT updates available$KERNEL. | $LIST --- $EXTRA_INFORMATION"
        exit $STATE_WARNING
    else
        echo "CRITICAL - $COUNT updates available$KERNEL. | $LIST --- $EXTRA_INFORMATION"
        exit $STATE_CRITICAL
    fi
fi