A "Nagios NRPE Check" refers to the use of the NRPE (Nagios Remote Plugin Executor) protocol in conjunction with the Nagios system to monitor and check remote resources and services on various servers. Nagios is a widely used open source system for monitoring networks, services and hosts.
NRPE allows Nagios to run plugins on remote hosts and return the results of plugin executions to the Nagios server. This enables decentralized monitoring of resources on different servers in the network.
Here are some key concepts related to the Nagios NRPE Check:
1. **NRPE Server:** The NRPE server is installed on the remote hosts to be monitored. This server allows Nagios to run specified plugins on the remote host.
2. **NRPE Plugin:** An NRPE plugin is an executable script or program that runs on the remote host and performs specific checks or tasks. For example, an NRPE plugin could check the status of CPU usage, memory usage, service status, or other parameters.
3. **Nagios Server:** The Nagios server coordinates monitoring and calls the NRPE plugins on the remote hosts. It receives the results of the plugin executions and evaluates them.
4. **Checks and Notifications:** Nagios can be configured to periodically perform checks on various remote hosts. If a check fails or exceeds a predefined threshold, Nagios can generate notifications to alert administrators of potential issues.
Using NRPE allows Nagios to collect detailed information about the health and performance of remote resources without having to perform all checks on a central Nagios server. This is particularly useful in distributed network environments where different servers and services need to be monitored.
It is important to note that NRPE should only be used safely. Communication between the Nagios server and the NRPE servers should be protected by appropriate security mechanisms to prevent unauthorized access.