From Wiki Centreon

Plugins are agent that nagios request to run. Often writen in shell or perl sctipts, they are designed to make interrogation of services or material that can be local or remote.

There are different ways to use plugins. They can be active (using snmp MIB or NRPE) or passive (using NSCA). More info about Nagios Plugins are available in the Nagios documentation.

Plugins are first of all designed to report info to Nagios, but Nagios can forward data that should be used by another application. This is possible when Nagios 'perfdata' has been properly configured.

Centreon developped its own plugins using RRDTool and Centreon's ServiceId to be able to graph data. Those plugins have all a name in 'chech_grap_(...)' and can only run with Centreon.

• any troubles with snmp (what is that stuff ?), have a look here (fr) :

http://christian.caleca.free.fr/snmp/

• a specific material to monitor, (what is its MIB ?), have a look here :

http://www.oidview.com/mibs/detail.html

More plugins

Nagios snmp plugins are available here

• http://nagios.manubulon.com/
• http://www.nagiosexchange.org/

Monitoring over openVZ

have a look here :

http://wiki.openvz.org/Monitoring_openvz_resources_using_nagios_and_snmp

and here (traffic monitoring on virtual machins) :

http://wiki.openvz.org/Traffic_accounting_with_iptables