Network Troubleshooting Tools (O'Reilly System Administration)

Over the years, thousands of tools have been developed for debugging TCP/IP networks. They range from very specialized tools that do one particular task, to generalized suites that do just about everything except replace bad Ethernet cables. Even better, many of them are absolutely free. There's only one problem: who has time to track them all down, sort through them for the best ones for a particular purpose, or figure out how to use them?

"Network Troubleshooting Tools" does the work for you--by describing the best of the freely available tools for debugging and troubleshooting. You can start with a lesser-known version of "ping" that diagnoses connectivity problems, or take on a much more comprehensive program like MRTG for graphing traffic through network interfaces. There's "tkined" for mapping and automatically monitoring networks, and Ethereal for capturing packets and debugging low-level problems.

This book isn't just about the tools available for troubleshooting common network problems. It also outlines a systematic approach to network troubleshooting: how to document your network so you know how it behaves under normal conditions, and how to think about problems when they arise, so you can solve them more effectively.

The topics covered in this book include:

Understanding your network

Connectivity testing

Evaluating the path between two network nodes

Tools for capturing packets

Tools for network discovery and mapping

Tools for working with SNMP

Performance monitoring

Testing application layer protocols

Software sources

If you're involved with network operations, this book will save you time, money, and needless experimentation.

Hooray for Joseph Sloan, who has written Network Troubleshooting Tools. Sloan's book catalogs--and evaluates, with intelligent and carefully researched commentary--scores of free utilities that have been developed for monitoring, managing, and troubleshooting TCP/IP networks large and small. As such, it's a guide to the tools of the network administration trade. Without the concentrated wisdom that's found here, a network administrator might take years to stumble across all the fantastically useful utilities described in these pages, and waste all kinds of effort in the process. This book has found an excellent niche: a high-level technical book that earns its cover price by applying an author's experience and research to stuff that's freely available online, thus adding to readers' abilities to exploit the free stuff that's out there.

The organization Sloan has chosen is interesting and efficient. Chapters deal with categories of utilities, such as packet sniffers and device mapping. Chapters begin with descriptions of the general purpose of utilities in their category and describe features (and alternate means of providing them) in general terms. Then come sections on utilities, complete with commentaries on the strengths of each and command-line dumps of the utilities in use. As utilities often are best used together, the author does a good job of showing what steps to take when that needs to be done. There's no companion CD-ROM, but the URLs that link to the utilities appear--sorted alphabetically by the programs' names, in an appendix. --David Wall

Topics covered: The free utilities--mostly for Unix variants--that the author has found to be most useful in his work as an administrator and troubleshooter of TCP/IP networks. Utilities for route tracing, packet sniffing, device detection, performance measurement, and other work are covered here.