Originally Published: Thursday, 3 May 2001 Author: Matt Michie
Published to: daily_feature/Linux.com Feature Story Page: 1/1 - [Std View]

Linux.com Book Review: Network Troubleshooting

Linux.com staff member Matt Michie takes a look at the latest doorstop: Network Troubleshooting by Othmar Kyas and finds that it's worth more than just a tool to kill mice.

At first glance, Network Troubleshooting by Othmar Kyas is an impressive tome. Clocking in at 1,000 pages in a nicely hard-bound cover, this is a book that has many purposes. This is the sort of book, when laid on a desk will shoot fear into non-technical managers and users. Carry this around with a nicely stocked tool-belt and a lineman's hand-set and you'll not only get a workout, but you'll probably get looks of respect.

On a more practical note, Network Troubleshooting is filled with useful material. Each of the layers in the OSI (Open Systems Interconnection) model is represented with design tips, and many common diagnostic techniques, and solutions for problems. Sprinkled liberally throughout are nicely done black and white graphics and figures.

For instance, in the first chapter, Network Availability, there is an excellent example on how to calculate the costs of network down time. This can be something that us techies are always aware of, but can't always put in terms a manager can understand. After making a nice spreadsheet with these techniques, you have a convincing tool you can present to management to get you the equipment you need to save the company money, and increase your uptimes.

The book seems to walk the line of theory and practicality fairly well. The author seems to understand that in order to troubleshoot the most difficult problems, the reader must understand the how and whys of the underlying network, but the author doesn't beat the reader over the head with too much theory.


Othmar Kyas is a clear writer, with a style that is useful to the people who actually are doing the network troubleshooting. The text is practical and feels "hands-on". For instance, here is an example from section 17.11:

Symptom: No Connection to FTP, Telnet Server

Cause (1): Incorrect user name (typing error, wrong keyboard driver, US/non-US keyboard layout)
Cause (2): Incorrect password (typing error, wrong keyboard driver, US/non-US keyboard layout)
Cause (3): User name, password changed
Cause (4): User account does not exist, no permission to log in
Cause (5): User account deleted
Cause (6): Mistyped or wrong IP address
Cause (7): TCP/IP driver misconfiguration
Cause (8): Domain name server incorrectly configured or not working (try to contact host by IP address)
Cause (9): Firewall blocks FTP or Telnet applications
Cause (10): FTP or Telnet client incorrectly configured for use across
firewall (no proxy configured; wrong FTP proxy configuration)
Cause (11): FTP or Telnet server down (does it respond to ping?)
Cause (12): No route available to FTP or Telnet server segment
(traceroute to server)

The book is also hardware and software independent. Although there are a very few screenshots of a windows troubleshooting program, the author carefully insures the solutions apply to whatever equipment the troubleshooter comes up against. The problems and solutions are non-specific to any one platform.


Unfortunately, Network Troubleshooting has a very poor index. With a book like this, readers are unlikely to sit down and read it cover to cover like a novel. It is more likely to be used as a reference when something particularly difficult to solve comes along. The first instinct of the troubleshooter will be to surf the index to move him directly to the section he needs to be in.

For a 1,000 page computer book to have a 9 page index is short-sighted. In fact, the Table of Contents is actually longer than the index! As a test case, I tried to find information on troubleshooting DHCP. It was not in the index, but I was able to find it fairly quickly in the Table of Contents. This seems like a major oversight in an otherwise complete book. Perhaps a later edition or the CD-ROM version would alleviate this problem.

In the appendix, a listing of the IEEE 802.3 Ethertype field codes starts on page 715 and goes to page 868, after which another 20 or 30 pages contain the Novell IPX Private Socket Numbers. Both of these are readily available on the Internet. There may be some small justification in including them, since if your network is down, there is no other way to find these tables. However, it seems more like an attempt to make the book seem more impressive by padding it to 1,000 pages exactly.

This seems to be a growing trend in technical publishing. If a book doesn't seem imposing, readers tend to overlook them on the shelf. Agilent isn't the only one guilty of this. Again, this probably makes more sense on a CD-ROM version.

The final downside is the hefty price, $95 for the hardcover and $395 for the CD-ROM. Thus, this may be out of reach for general users, however corporate network troubleshooters can probably justify the price.


I would recommend this book to anyone who deals with networks and the problems they cause. The subject covered is broad enough to affect sysadmins, Internet Service Providers, Internet hosting companies, advanced home users, and almost anything on an "enterprise" network.

Despite some minor glitches, this book is a good show from Agilent, and will no doubt find its place on bookshelves throughout server rooms.

Title: Network Troubleshooting
Author: Othmar Kyas
Publisher: Agilent Technologies Publication
ISBN: 0-9703331-0-2

Table of Contents