By James Mohr
Nagios is a powerful and flexible monitoring tool. I have been using Nagios professionally for about two years, and up to now, the only good documentation provided was the references on the Nagios website (www.nagios.org) and posts to various mailing lists and forums. However, that situation has recently changed for the better.
I was really excited when I found out that a book on Nagios ha released. By coincidence, two books on the subject of Nagios came out at almost the same time, which got me even more excited. Because of the complexity of Nagios and the content of both of these books, I decided to do something a little different this month and provide a head-to-head comparison. The first is book in this Nagios set is Pro Nagios 2.0 from Apress, and the second book is Nagios: System and Network Monitoring from No Starch Press.
Both books start with the basic installation and configuration of Nagios. Since you are not going to find a pre-compiled version for every operating system, both go into the specifics of compiling the source code. Each talks about the basic directory structure, but what is missing is a detailed description of the various "support" files, such as log files and so forth. This topic should have been addressed, because you are going to need to be able to interpret this information when troubleshooting.
Both books also suffer from the common problem of having a shortage of useful graphics. Naturally, there are screenshots from the web interface, but you'll find few graphics detailing the functionality. In both cases, I got the feeling that many of the graphics in the book were inserted simply to break up the text.
Nagios is a very complex product with many different layers and interactions. For someone just starting out, it is often difficult to keep track of things when all you have is a text description, so good graphics are essential to a book on Nagios.
Each book is beneficial for both the newbie and the more experienced Nagios admin. It is difficult to say which one is "better" is any absolute sense, as they approach the material in different ways. Having used Nagios for a while, I am fairly familiar with the various configuration files and directives. Since these files and directives are described in great detail in other places, I personally do not have as much need for a reference work like Nagios: System and Network Monitoring. Therefore, I got more out of Pro Nagios 2.0, as it helped me clear up a few things and pointed out some potential problems. However, I would not say that you should avoid the other book if what you are looking for is a good reference, particularly if you are just starting out.
If you consider how important system monitoring is to any company, you'll realize that doing it right is essential. If you aren't currently proficient with Nagios, and you know you will need to be sometime soon, it would definitely be worthwhile to invest the money to get both these books for their unique approaches to the topic.
Since I was already familiar with the author's book Hardening Linux, I was particularly excited to hear he had written a book on Nagios. When it arrived, I must say that I was not disappointed. Although Nagios might be fairly straight forward to configure once you get the basics down, it is definitely not straight forward to configure efficiently. The author does a great job of getting you to that point.
This book is better organized than the No Starch book, and the chapters build well upon previous material. The book is also filled with blocks with tips and words of caution.
Each chapter ends with a section entitled "Checkpoint," which lists the key aspects of the chapter and provides a nice review. This is followed by a list of resources where you can find more information about the topics.
The final chapter of the book is on developing Nagios plug-ins. Although this chapter could have been improved with more details on a couple of topics, it does provide good background on what is needed to extend Nagios to its fullest.
The only real downside of Pro Nagios 2.0 is that it is not a very good reference. That is, if you are looking for a quick refresher about a specific option or directive, it is not always easy to find the answer quickly.
James Turnbull
400 Pages
APress
1-590596099
£ 33.99, US$ 49.99, EUR 44.50
I might be tempted to say that this is "simply" a re-hash of existing material. That is not necessarily a bad thing because the available information is spread out through a number of different sources. Having the information available in a single reference is a useful, and the author does a good job of providing the necessary information in an easy-to-access and easy-to-understand form.
With this book, the keyword is "reference." While I did find the text a little lacking in real-world, practical information, it does provide easy access to a wide range of directives in various configuration files. If you are just starting out with Nagios, this is useful to help you either modify the existing example configuration files or create your own.
The book is a translation from German and, unfortunately, this shows through in a few places. All too frequently in English translations from German, the translator tries too hard to keep the original German sentence structure. The result is sentences that are often longer and often more convoluted than they would normally be in English, making the text difficult to understand. Being fluent in German, I could usually "rebuild" the original German and then translate that into English. Unfortunately, not everyone can do this, so some parts are real stumbling blocks. There are also a couple of places that, despite my German and my experience with Nagios, I wasn't sure what was being said. However, I must add that an email to the original German publisher was answered by the publisher himself the same day, and he assured me he would address these issue in the next printing.
Another thing that bothered me were "gotchas" that are mentioned only once, almost in passing, at the beginning of the book where you are already overwhelmed by the new terms and functionality. The book would definitely be more useful if the author would have reminded us of these issues when he went into the details in later chapters.
I also felt that the book could have been well served by more time on the Nagios "core" and less on add-ons and extras. Although these topics are useful, it is important that the book have a well define scope. Also, describing how to use Nagios to monitor SAP is useful if you happen to be running SAP, but the vast majority of Nagios users are not running SAP. Thus, this is all space that should have been put to a different use.
Despite the negative overtones, I still feel this is a useful book.
Wolfgang Barth
462 Pages
No Starch Press
1-59327-070-4
£ 30.99, US$ 44.95, EUR 36.89