Book Image

Nagios Core Administration Cookbook

By : Tom Ryder
Book Image

Nagios Core Administration Cookbook

By: Tom Ryder

Overview of this book

Network monitoring requires significantly more than just pinging hosts. This cookbook will help you to comprehensively test your networks' major functions on a regular basis."Nagios Core Administration Cookbook" will show you how to use Nagios Core as a monitoring framework that understands the layers and subtleties of the network for intelligent monitoring and notification behaviour. Nagios Core Administration Guide introduces the reader to methods of extending Nagios Core into a network monitoring solution. The book begins by covering the basic structure of hosts, services, and contacts and then goes on to discuss advanced usage of checks and notifications, and configuring intelligent behaviour with network paths and dependencies. The cookbook emphasizes using Nagios Core as an extensible monitoring framework. By the end of the book, you will learn that Nagios Core is capable of doing much more than pinging a host or to check if websites respond.
Table of Contents (18 chapters)
Nagios Core Administration Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Using an alternative check command for hosts


In this recipe, we'll learn how to deal with a slightly tricky case in network monitoring—monitoring a server that doesn't respond to PING, but still provides some network service that requires checking.

It's good practice to allow PING where you can, as it's one of the stipulations in RFC 1122 and a very useful diagnostic tool not just for monitoring, but also for troubleshooting. However, sometimes servers that are accessed only by a few people might be configured not to respond to these messages, perhaps for reasons of secrecy. It's quite common for domestic routers to be configured this way.

Another very common reason for this problem, and the example we'll address here, is checking servers that are behind an IPv4 NAT firewall. It's not possible to address the host directly via an RFC1918 address, such as 192.168.1.20, from the public Internet. Pinging the public interface of the router therefore doesn't tell us whether the host for which it...