Nagios/Icinga nf_conntrack_count check

check_nf_conntrack_count

#!/bin/sh                                                                                                                 [0/329]

# takes warning and critical percentage as $1 and $2 parameters
# if not specified defaults to 95% and 97% respectivley

STATUS_CRITICAL=1
STATUS_WARNING=2
STATUS_OK=0

WARNING_LEVEL=${1:-95}
CRITICAL_LEVEL=${2:-97}

MAX_CONNTRACK=`/sbin/sysctl -n net.netfilter.nf_conntrack_max`
REAL_CONNTRACK=`/sbin/sysctl -n net.netfilter.nf_conntrack_count`

# warning 95% max, critical 97% max
WARNING=$(( $MAX_CONNTRACK / 100 * $WARNING_LEVEL))
CRITICAL=$(( $MAX_CONNTRACK / 100 * $CRITICAL_LEVEL))


if [ $REAL_CONNTRACK -gt $CRITICAL ]
then
 echo "CRITICAL - Conntrack Table Almost Full. Actual: $REAL_CONNTRACK Max: $MAX_CONNTRACK"
 exit $STATUS_CRITICAL
else
 if [ $REAL_CONNTRACK -gt $WARNING ]
 then
  echo "WARNING - Conntrack Table Almost Full. Actual: $REAL_CONNTRACK Max: $MAX_CONNTRACK"
  exit $STATUS_WARNING
 else
  echo "OK - Conntrack Table Actual: $REAL_CONNTRACK Max: $MAX_CONNTRACK"
  exit $STATUS_OK
 fi
fi