We are all aware of the importance of computers in our lives, and the problems that can ensue when they fail. Computer monitoring systems do just as their name suggests: they monitor computers and networks for problems, and notify administrators when something goes awry. Commercial computer monitoring systems are large, complex, and expensive pieces of software. An alternative to these expensive commercial monitoring systems is the Nagios open-source solution.

Nagios manages scheduling and notification for a collection of monitoring modules that can deliver the same functions as commercial tools, but without the high price tag. However, embarking on the installation of any monitoring solution is not simple. With any solution, Nagios included, significant technical effort is required to design, install, configure, and effectively run these systems.

The author of this book begins with an explanation of best practices in system and network monitoring, and details the operation of the various components of monitoring systems. The discussion covers what these systems monitor (such as ports and applications) and the plug-ins that Nagios uses to accomplish this. These first two chapters should be useful to both technical and management readers alike, as they help build an understanding of how monitoring systems work and what they can achieve.

Chapter 3 covers Nagios installation and chapter 4 covers configuration. Chapter 5 expands on configuration, giving more detail on the tweaking of configuration files and scripting templates. In chapter 6, examples of some common monitoring plug-ins are given. The author describes ping, port queries, and working with the simple network management protocol (SNMP), and provides detailed examples for monitoring Microsoft Windows systems. Chapter 7 looks at options for scaling Nagios to monitor a large computing infrastructure, and chapter 8 looks at displaying the output of the monitoring tools and visualizing the state of networks and systems for humans. Chapter 9 introduces Nagios XI, a commercial version of the software that tries to simplify much of the technical complexity, and chapter 10 describes the internal workings of the Nagios Event Broker in an effort to encourage further community development.

Although the book is aimed at technical specialists, if you just need to understand what system and network monitoring is all about, you can get that from chapter 1. If you want a little more detail on operational aspects of monitoring systems, then continue on through chapter 2. If you need to be able to design, install, configure, and operate a Nagios monitoring system, the rest of the book is for you. A thorough table of contents and a good index make the book useful as a reference as well.

There are quite a number of books available on Nagios. Unlike many of the others, which simply provide a technical description of Nagios, the approach in this book is more holistic, providing a top-down approach with more emphasis on initial design rather than diving straight into the technology. The author first introduces the management objectives of monitoring and then moves into the more technical details needed to construct a nontrivial monitoring system.

More reviews about this item: Amazon