check_mount

#!/bin/bash

. $(dirname $0)/lib.sh

while getopts "m:c:w:" OPT; do
	case $OPT in
		m) MOUNT=$OPTARG ;;
		w) WARNING_PERC=$OPTARG ;;
		c) CRITICAL_PERC=$OPTARG ;;
	esac
done

if [ -z "$MOUNT" -o -z "$WARNING_PERC" -o -z "$CRITICAL_PERC" ]; then
	echo "Usage: $0 -m <mount point> -w <warning percentage>" \
			"-c <critical percentage>"
	exit $STATE_UNKNOWN
fi

# First check to see if it's mounted
if [ -z "$(awk '$2 == "'$MOUNT'" { print }' /proc/mounts)" ]; then
	echo CRITICAL - Not mounted: $MOUNT
	exit $STATE_CRITICAL
fi

read AVAILABLE_BL TOTAL_BL FREE_BL BS <<< $(stat -fc '%a %b %f %S' $MOUNT)

# Multiply the reported block counts by the fundamental block size to get the
# values in bytes.
AVAILABLE=$((AVAILABLE_BL * BS))
TOTAL=$((TOTAL_BL * BS))
FREE=$((FREE_BL * BS))

# Compute some other useful values and the main 'fullness' percentage. We use
# full to mean there is no available space left, in other words: less than the
# amount of reserved blocks is free on the file system. It is the same
# percentage df reports as 'Use%' (but truncated instead of rounded).
USED=$((TOTAL - FREE))
RESERVED=$((FREE - AVAILABLE))
USABLE=$((TOTAL - RESERVED))
FULLNESS_PERC=$((100 * USED / USABLE))

INFO="$FULLNESS_PERC% full, $(bytes_to_human_bi $USED) used, \
$(bytes_to_human_bi $AVAILABLE) available - filesystem: \
$(bytes_to_human_bi $RESERVED) reserved, $(bytes_to_human_bi $USABLE) usable"
PERF="used=${USED}B;$((USABLE * WARNING_PERC / 100));\
$((USABLE * CRITICAL_PERC / 100)) usable=${USABLE}B total=${TOTAL}B"

if [ $FULLNESS_PERC -ge $CRITICAL_PERC ]; then
	STATE="CRITICAL";
elif [ $FULLNESS_PERC -ge $WARNING_PERC ]; then
	STATE="WARNING";
else
	STATE="OK";
fi

echo "$STATE - $INFO|$PERF"

eval exit \$STATE_$STATE