#!/bin/bash

UNKNOWN=3
OK=0
WARNING=1
CRITICAL=2

HOST=${1}
COMM=${2}

if [[ ${HOST} == "" || ${COMM} == "" ]]
then
        echo "Usage: check_kernel.sh host.ip.adr.res snmp-community"
        exit ${UNKNOWN}
fi

KERNEL=`/usr/bin/snmpwalk -v2c -c ${COMM} ${HOST} sysDescr | /bin/cut -d'=' -f2 | /bin/sed -e "s/ STRING: Linux //g" | /bin/awk '{for(i=2; i<NF; i++) printf "%s ",$i; print $NF}'`

if [[ -z ${KERNEL} ]]
then
        echo "Timeout: No Response from ${HOST}"
        exit ${CRITICAL}
fi

if [[ -n ${KERNEL} ]]
then
        echo "${KERNEL}"
        exit ${OK}
fi