Xmodule published a Nagios tutorial
Nagios comes with a wide range of built-in scripts for monitoring services. This tutorial will cover the process of using some of these scripts for checking common services, such as MySQL, Apache web server, DNS, etc.How to monitor common services with Nagios
To keep the article focused on service monitoring, we will not be configuring hostgroups or templates, as they have been covered in a previous tutorial. Nonetheless, they can be tuned to match the requirements.