Network Troubleshooting Tools
Book Review

By Dale Farris, Secretary Golden Triangle PC Club February 2003 General Overview This book is not a general introduction to network troubleshooting. Rather, it is about one aspect of troubleshooting, information collection. The book is a tutorial introduction to tools and techniques for collecting information about computer networks. It should be particularly useful when dealing with network problems, but the tools and techniques it describes are not limited to troubleshooting. Many can and should be used on a regular basis regardless whether you are having problems. The author's attempt is to assist network administrators in their proactive approach to heading off problems, with an emphasis on using these tools before problems occur. The tools can be classified as network management or network performance analysis tools. Author Sloan does not catalog every possible tools, as there are simply too many already available and the number continues to grow. He focuses on the tools he believes are the most useful, a collection that should help in dealing with almost any problem faced by network administrators. In many cases, he describes more than one tool for a particular job, since it is rare for two tools to have exactly the same features. One tool may be more useful than another, depending on circumstances. Because of the differences in operating systems, a specific tool may not be available on all systems. So, it is work knowing the alternatives. The tools are freely available Unix tools, and many are open source tools covered by GNU- or BSD-style licenses. In selecting the tools, his first concern has been availability. He has given the highest priority to the standard Unix utilities. Next in priority are tools available as packages or ports for FreeBSD or Linux. Tools requiring separate compilation or available as binaries were given a lower priority since these may be available on fewer systems. In some cases, PC-only tools and commercial tools are noted but not discussed in detail. The bulk of the book is specific to Ethernet and TCP/IP, but the general approach and many of the tools can be used with other technologies. While the book is mainly about Unix tools, at the end of the chapters, he also includes a brief section for Windows users. These sections are included since even small networks usually include a few computers running Windows. These sections are not to meant to be definitive. These are provided as starting points, a quick overview of what is available. A wide range of tools are described. Many are designed to do one thing, while others are extremely complex tools. The author does not attempt to provide a comprehensive treatment for each tool, as this would bulk up the book by a factor of at least 3 x. Some tools have manuals and other documentation that easily exceed the size of this book. Most have additional documentation that you will want to retrieve once you begin to use the tool. The author's goal is to make you aware of the tools and to provide you with enough information that you can decide which ones may be useful to you and in what context, so that you can get started using the tools. Each chapter centers on a collection of related tasks or problems and tools useful for dealing with these tasks. The discussion is limited to features that are relevant to the problem being discussed. Consequently, the same tool may be discussed in several places in the book. Key Topics How to understand your network Connectivity testing How to evaluate the path between two network nodes Tools for capturing packets Tools for network discovery and mapping Tools for working with SNMP Performance monitoring How to test application layer protocols Software sources Table of Contents The book is organized into twelve (12) chapters, plus two (2) appendixes. The twelve (12) chapters include the following titles. Network Management and Troubleshooting Host Configurations Connectivity Testing Path Characteristics Packet Capture Device Discovery and Mapping Device Monitoring with SNMP Performance Measurement Tools Testing Connectivity Protocols Application-Level Tools Miscellaneous Tools Troubleshooting Strategies The two appendixes include Appendix A, Software Sources, and Appendix B, Resources and References. Target Readers The focus of this book is to serve the needs of individuals new to network administration. The book should also be of use to those who have inherited responsibility for existing systems and networks set up by others. The book is designed to help these folks acquire the additional information needed to do their job. With this in mind, the added bonus of the Appendix of resources is alone worth the investment in the book. Here, author Sloan provides URL's for all the described tools, along with an additional collection of information on all sorts of outside references and helpful organizations. Book Contents 369 pages; preface; acknowledgments; figures; tables, tips; screen shots; appendixes; index; cover colophon Author Joseph D. Sloan About the Author Joseph D. Sloan has been working with computers since the mid-1970s. He began using Unix as a graduate student in 1981, first as an applications programmer and later as a system programmer and system administrator. Since 1988 he has taught mathematics and computer science at Lander University. He also manages the networking computer laboratory at Lander, where he can usually be found testing and using the software tools described in this book. ISBN August 2001, First Edition 0-596-00186-X List Price $39.95 $59.95 CAN Publisher Contact Marsee Henon marsee@oreilly.com O'Reilly & Associates, Inc. 1005 Gravenstein Highway North Sebastopol, California 95472 707-827-7000 800-998-9938 FAX 707-829-0104 www.oreilly.com