The Nagios is one of the most poplur product for monitoring IT Infrastructure, such as servers, network and services.
The system overview of the Nagios modules:
- Nagios Core - The Server with Monitor GUI.
- NRPE (Nagios Remote Plugin Executor) - The communication handler between server and client/agent.
- Nagios Plugins - Client or Agent that do the actual monitoring, e.g. check server load or if service is running.
Remember Nagios is not supported by Red Hat and installing Nagios from EPEL repository, is on you own risk. But if you think of the alternative, which is installing Nagios from source and compiling it with gcc is not an attractive alternative. Since then you have to manually uphold the patch level you want in production. And beside you do not want to have the gcc compiler installed in production, due to security risks.
For manual installation see http://nagios.sourceforge.net/docs/3_0/quickstart-fedora.html.
Install the EPEL (Extra Packages for Enterprise Linux) repository. [https://fedoraproject.org/wiki/EPEL]
Install the Nagios Core and all plugins.
Start Nagios Server.
Start Nagios Server Web GUI.
Nagios Core Web GUI
To change the default password for admin, see /etc/httpd/conf.d/nagios.conf.
Reference for htpasswd - Manage user files for basic authentication. [http://httpd.apache.org/docs/2.2/programs/htpasswd.html]
The Nagios main configuration file.
The Nagios Core Admin Server is built with CGI scripts.
HTTPD configuration for Nagios Core