Overview

JNRPE provides a Java and a Javascript (Node.js) implementation of the NRPE server. The main features of JNRPE are:

• Execute existing plugins: by using JNRPE you won't lose the huge amount of already existing Nagios plugins
• Write plugins with JAVA or Javascript: while current plugins must be compiled for every platform you need to run them on, JNRPE plugins can be used everywhere without any need to recompile
• Execute the Java/Javascript plugins directly inside JNRPE: no new JVMs will be instantiated to execute java plugins.

How it works

1. Nagios will invoke a check defined as a check_nrpe command.
2. check_nrpe will invoke the command on the JNRPE server
3. The JNRPE server will invoke the plugin associated with the requested command
4. The plugin will perform the check. If the plugin is the NATIVE check plugin (former EXEC), the external executable will be invoked and its output will be returned. This plugin is useful if you need to use a mix of java/javascript and executable plugins since you don’t have to install both JNRPE and NRPE.
5. JNRPE receives the plugin output and returns it to check_nrpe
6. check_nrpe returns the check result to Nagios