#!/usr/local/bin/bash
#
# check_iostat_bsd - Nagios device statistics check script (perfdata only)
# version 1.0   14.11.2012
# by Mikanoshi - iam@mikanoshi.name, http://en.mikanoshi.name
# tested on FreeBDS 8.3
#
# This Nagios plugin is free software, and comes with ABSOLUTELY NO WARRANTY.
# It may be used, redistributed and/or modified under the terms of the
# GNU General Public Licence (see http://www.fsf.org/licensing/licenses/gpl.txt).

STATE_OK=0
STATE_WARNING=1
STATE_CRITICAL=2
STATE_UNKNOWN=3

IOSTAT=`which iostat 2>/dev/null`
AWK=`which awk 2>/dev/null`
GREP=`which grep 2>/dev/null`
TAIL=`which tail 2>/dev/null`

TEMP="/var/spool/nagios/iostat.`date +'%s'`.tmp"
GET_TPS=FALSE
GET_TPS_READS=FALSE
GET_TPS_WRITES=FALSE
GET_READS=FALSE
GET_WRITES=FALSE
GET_DUR=FALSE
COUNT=3
RESULT=""
RESULT_EXIT=$STATE_OK

function usage {
	printf "\nUsage: check_iostat_bsd -n <samples count> -d <device> -t|r|s|i|o|a\n"
	printf "\nDevice: run iostat -x and find your device name in the first column, example: -d aacd0\n"
	printf "	-n	Samples count (default=3, first is not taken into account)\n"
	printf "	-r	read operations per second\n"
	printf "	-s	write operations per second\n"
	printf "	-t	IO transactions per second (read+write)\n"
	printf "	-i	kilobytes read per second\n"
	printf "	-o	kilobytes write per second\n"
	printf "	-a	average duration of transactions, in milliseconds\n"
	printf "\n	t, r, s, i, o, a parameters can be used in any combinations, e.g.:\n	check_iostat_bsd -n 5 -d aacd0 -t -r -s -i -o -a\n"
}
 
function doreturn {
	rm -f $TEMP
	echo $RESULT
	exit $RESULT_EXIT
}

function doargs {
	if (`test $# -gt 0`)
	then
		while getopts n:d:trsioah argcase "$@"
		do
			case $argcase in
				d)	DEVICE=$OPTARG;;
				n)	COUNT=$OPTARG;;
				t)	GET_TPS=TRUE;;
				r)	GET_TPS_READS=TRUE;;
				s)	GET_TPS_WRITES=TRUE;;
				i)	GET_READS=TRUE;;
				o)	GET_WRITES=TRUE;;
				a)	GET_DUR=TRUE;;
				*)	usage
					exit;;
			esac
		done
	else
		usage
		exit
	fi
}

doargs $@

if [ ! -f $IOSTAT ] ; then
	RESULT="ERROR: iostat cannot be found!"
	RESULT_EXIT=$STATE_UNKNOWN
	doreturn
fi

if [ $COUNT -ge 2 ] ; then
	$IOSTAT -x -K $DEVICE 1 $COUNT | $GREP $DEVICE| $TAIL -`expr $COUNT - 1` > $TEMP
else
	RESULT="ERROR: Samples number must be > 1 (default 3)"
	RESULT_EXIT=$STATE_UNKNOWN
	doreturn
fi

if [ $GET_TPS = "TRUE" ] ; then
	TPS=`cat $TEMP | $AWK '{ sum += $2 + $3 } END { print sum / NR } '`
	PERF=" tps=$TPS;;;"
fi

if [ $GET_TPS_READS = "TRUE" ] ; then
	TPSR=`cat $TEMP | $AWK '{ sum += $2 } END { print sum / NR } '`
	PERF=$PERF" tpsr=$TPSR;;;"
fi

if [ $GET_TPS_WRITES = "TRUE" ] ; then
	TPSW=`cat $TEMP | $AWK '{ sum += $3 } END { print sum / NR } '`
	PERF=$PERF" tpsw=$TPSW;;;"
fi

if [ $GET_READS = "TRUE" ] ; then
	READS=`cat $TEMP | $AWK '{ sum += $4} END { print sum / NR } '`
	PERF=$PERF" reads="$READS"KB;;;"
fi

if [ $GET_WRITES = "TRUE" ] ; then
	WRITES=`cat $TEMP | $AWK '{ sum += $5} END { print sum / NR } '`
	PERF=$PERF" writes="$WRITES"KB;;;"
fi

if [ $GET_DUR = "TRUE" ] ; then
	DUR=`cat $TEMP | $AWK '{ sum += $7} END { print sum / NR } '`
	PERF=$PERF" svc_t=$DUR;;;"
fi

RESULT="OK - data received |$PERF"
RESULT_EXIT=$STATE_OK

doreturn