10.2. Configuring SNMP with the Red Hat High Availability Add-On

To configure SNMP with the Red Hat High Availability Add-On, perform the following steps on each node in the cluster to ensure that the necessary services are enabled and running.

To use SNMP traps with the Red Hat High Availability Add-On, the snmpd service is required and acts as the master agent. Since the foghorn service is the subagent and uses the AgentX protocol, you must add the following line to the /etc/snmp/snmpd.conf file to enable AgentX support:
```
master agentx
```
To specify the host where the SNMP trap notifications should be sent, add the following line to the to the /etc/snmp/snmpd.conf file:
```
trap2sink host
```
For more information on notification handling, see the snmpd.conf man page.
Make sure that the snmpd daemon is enabled and running by executing the following commands:
```
# chkconfig snmpd on
# service snmpd start
```
If the messagebus daemon is not already enabled and running, execute the following commands:
```
# chkconfig messagebus on
# service messagebus start
```
Make sure that the foghorn daemon is enabled and running by executing the following commands:
```
# chkconfig foghorn on
# service foghorn start
```
Execute the following command to configure your system so that the COROSYNC-MIB generates SNMP traps and to ensure that the corosync-notifyd daemon is enabled and running:
```
# echo "OPTIONS=\"-d\" " > /etc/sysconfig/corosync-notifyd
# chkconfig corosync-notifyd on
# service corosync-notifyd start
```

After you have configured each node in the cluster for SNMP and ensured that the necessary services are running, D-bus signals will be received by the foghorn service and translated into SNMPv2 traps. These traps are then passed to the host that you defined with the trapsink entry to receive SNMPv2 traps.