Overview
Agents are programs that help aid Nagios with monitoring. Most often they are used to get information from remote machines or devices.
Agents
There are several agents for Nagios, generally the agents work with Nagios Core and Nagios XI but it is the ease of install and use that differentiates Nagios XI from Nagios Core. Some agents are provided by and supported by Nagios, and some are from third parties.
Here is a list of some popular agents with links more more information.
NCPA - Nagios Cross Platform Agent
NRPE - Nagios Remote Plugin Executor
NSCA - Nagios Service Check Acceptor
There are many more available in the Nagios Exchange under Addons.
Additional Info
Final Thoughts
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