Nagios Core Administration Cookbook

Setting up a redundant monitoring host

In this recipe, we'll learn how to implement a simple kind of redundancy for Nagios Core, by running a second Nagios Core instance with a near-identical configuration on another machine.

This may seem like it would not need a recipe to implement. It should be reasonably straightforward to simply copy over the configuration for a Nagios Core system and run it concurrently. There are two main problems with this:

• Every problem detected on the network will fire notifications events twice. The administrator charged with looking after the pager might well find this unbearable!
• Everything will be checked twice. On smaller networks with simple checks, this may not be too much of a concern, but it could be an issue on ...