5. Optional - Configure Cluster Alerting Using Nagios

For each of the newly added slave node, complete the following instructions in order to use Nagios for cluster alerting:

  1. On the Nagios server, add the host definition to the /etc/nagios/objects/hadoop-hosts.cfg file:

  2. On the Nagios server, edit the /etc/nagios/objects/hadoop-hostsgroups.cfg file.

    Add hostnames of the newly added slave nodes to members list under the slaves host group.

  3. Restart the Nagios server:

    service nagios start