Nagios Core is an open-source monitoring tool for networks, services, and applications, using the NRPE agent to collect metrics (disk, CPU, network) from remote hosts and report them on a web dashboard. This guide compiles Nagios Core from source on Ubuntu 24.04, installs plugins, and configures it to monitor a separate remote host.
Prerequisites: two Ubuntu 24.04 servers — one for Nagios, one as the monitored remote host.
Compile and Install Nagios Core
Not packaged for Ubuntu — build from source.
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