An interesting post on securing Nagios!
Nagios is a monitoring software designed to let you know about problems on your hosts and networks quickly. You can configure it to be used on any network. Setting up a Nagios server on any Linux distribution is a very quick process however to make it a secure setup it takes some work. This article will not show you how to install Nagios since there are tons of them out there but it will show you in detail ways to improve your Nagios security.
Read more here : http://www.linuxsecurity.com/content/view/144088