Abstract
In this post we'll see how to monitor a Cisco WAAS using Nagios and SNMP. There are a lot of SNMP information available, but we want to check: alert and warning messages and active connections (must be lower than licensed ones).
Cisco WAAS OIDs
The official manual shows which are the OID we need:
- Messages:
- cceAlarmCriticalCount (1.3.6.1.4.1.9.9.178.1.6.2.1): The value of this object specifies the number of alarms currently raised with a severity of “critical”.
- cceAlarmMajorCount (1.3.6.1.4.1.9.9.178.1.6.2.2): The value of this object specifies the number of alarms currently raised with a severity of “major”.
- cceAlarmMinorCount (1.3.6.1.4.1.9.9.178.1.6.2.3): The value of this object specifies the number of alarms currently raised with a severity of “minor”.
- Connections
- cwoTfoStatsMaxActiveConn (1.3.6.1.4.1.9.9.762.1.2.1.3): This object contains maximum number of active TCP connections that this device can optimize.
- cwoTfoStatsActiveOptConn (1.3.6.1.4.1.9.9.762.1.2.1.2): This object contains number of currently active TCP connections getting optimized.
- cwoTfoStatsActivePTConn (1.3.6.1.4.1.9.9.762.1.2.1.10): This object contains number of active Pass Through TCP connections. Connections which are not selected for optimization are called Pass Through.
We check connection values first. Active, Maximum and Pass-Through connections are fetched using snmpgetnext:
OUTPUT=$(snmpgetnext -m /dev/null -c $COMMUNITY -v $VERSION $HOST $cwoTfoStatsMaxActiveConn $cwoTfoStatsActiveOptConn $cwoTfoStatsActivePTConn)
Then output is parsed:
MAX=$(echo $OUTPUT | sed 's/.*: \([0-9]*\) .*: \([0-9]*\) .*: \([0-9]*\)/\1/')
OPT=$(echo $OUTPUT | sed 's/.*: \([0-9]*\) .*: \([0-9]*\) .*: \([0-9]*\)/\2/')
PT=$(echo $OUTPUT | sed 's/.*: \([0-9]*\) .*: \([0-9]*\) .*: \([0-9]*\)/\3/')
And finally the right status is raised:
CURRENT_PERC=$(echo "100*($OPT)/$MAX" | bc)
WARNING=$(echo "$MAX*0.$WARNING_PERC" | bc)
CRITICAL=$(echo "$MAX*0.$CRITICAL_PERC" | bc)
if [ "$CURRENT_PERC" -ge "$CRITICAL_PERC" ]; then
STATUS="CRITICAL"
RC=2
elif [ "$CURRENT_PERC" -ge "$WARNING_PERC" ]; then
STATUS="WARNING"
RC=1
elif [ "$CURRENT_PERC" -ge 0 ]; then
STATUS="OK"
RC=0
else
STATUS="UNKNOWN"
RC=3
fi
On the second step Critical, Major and Minor alerts are fetched:
vOUTPUT=$(snmpgetnext -m /dev/null -c $COMMUNITY -v $VERSION $HOST $cceAlarmCriticalCount $cceAlarmMajorCount $cceAlarmMinorCount)
Then output is parsed:
MSG_CRITICAL=$(echo $OUTPUT | sed 's/.*: \([0-9]*\) .*: \([0-9]*\) .*: \([0-9]*\)/\1/')
MSG_MAJOR=$(echo $OUTPUT | sed 's/.*: \([0-9]*\) .*: \([0-9]*\) .*: \([0-9]*\)/\2/')
MSG_MINOR=$(echo $OUTPUT | sed 's/.*: \([0-9]*\) .*: \([0-9]*\) .*: \([0-9]*\)/\3/')
And the right status is raised, according to the previous one:
if [ "$MSG_CRITICAL" -gt 0 ] && [ "$RC" -le 3 ]; then
STATUS="CRITICAL"
RC=2
elif [ "$MSG_MAJOR" -gt 0 ] && [ "$RC" -le 2 ]; then
STATUS="WARNING"
RC=2
fi
The last line of the script prints a messages and performance data:
echo -n "$STATUS (Msg $MSG_CRITICAL/$MSG_MAJOR/$MSG_MINOR) - Connections $OPT/$MAX (PT=$PT) | conn=$OPT;$WARNING;$CRITICAL;0;$MAX"
exit $RC
Performance data must be in the following form: varname=value;warn;crit;min;max
Configuring check_waas within Nagios
Nagios users should be able to integrate check_waas in a Nagios environment. A command template should be defined:
define command {
#$ARG1$: SNMP Version
#$ARG2$: SNMP Community
#$ARG3$: Warning Limit (connections)
#$ARG4$: Critical Limit (connections)
command_name check-waas
command_line $USER1$/check_waas -H $HOSTADDRESS$ -v $ARG1$ -C $ARG2$ -w $ARG3$ -c $ARG4$
}
Then a service must be added to a host:
define service {
use generic-service
host_name wave.example.com
service_description WAAS status
check_command check-waas!2c!public!75!90
servicegroups waas-status
}
Other configurations are missing, please refers to the Nagios manuals.
