Your Approach to Troubleshooting

Troubleshooting is really an art and definitely an acquired skill. Every network has its own particular quirks (just like a used car), and actually maintaining a particular network is the best way to accumulate the information needed to enable you to troubleshoot that network when problems rear their ugly heads.

One way to make troubleshooting problems a little easier is to keep good documentation related to the network. This includes server configurations, network client configurations, and problems that you have experienced and then solved . Even in cases where you are working with a relatively small network, some sort of map that shows how the network cabling has been run and the addressing of the network devices can be a big help in troubleshooting situations.



A number of companies make time domain reflectometers, such as Agilent Technologies at These devices are expensive (I'm talking a couple of thousand dollars or more) and the best way to learn more about how they work is to check out the Agilent product line (their site includes operating manuals) or do a search for time domain reflectomer using your Web browser. Voltmeters are inexpensive devices and can be picked up at just about any hardware or electrical supply store.

When actually attempting to solve a problem on the network, try to use a systematic approach to problem solving. First, identify the problem; then gather facts related to the problem. You might want to make a list of the possible hardware and software failures that can cause a particular problem.

Then, systematically go through your list of possible causes one at a time and troubleshoot the problem. This is a much better approach than the "shotgun" approach, where you run around and change a bunch of server and client settings and physical connections all at once. This never allows you to pinpoint the actual cause of the problem. The problem just kind of goes away (because you fixed it with one of the many solutions you implemented). If the problem appears again, rather than immediately being able to provide the correct solution, you will again have to result to voodoo and run through a whole list of fixes.

As you are working through the list of possible problems, you will find that a good, general approach to troubleshooting is to work from the basic to the complex. Check things that will result in a simple fix; for example, make sure the power cables are connected on computers, hubs, and other network devices before assuming the problem is a complex NOS configuration problem with the server. In many cases a disconnected cable or an unplugged hub, rather than a malfunctioning server, will be causing the problem on the LAN.

Troubleshooting basic issues first also allows you to attempt to fix the network without getting way over your head in terms of software and hardware configurations. If you reach a point as you tick off basic issues that could cause the problem where you are in unfamiliar territory, you might wish to call your software or hardware vendor for technical support. There is no disgrace (even for the seasoned network administrator) to try to get help in solving a network problem.

The Absolute Minimum

In this chapter we took a look at some of the basics of troubleshooting a network. We discussed issues related to your network users and looked at the monitoring of server hardware and the network.

  • Monitoring hardware and establishing baselines allows you to determine whether hardware on a server (such as the processor and memory) is being overtaxed and could lead to server failure.

  • Tools such as the Windows Server Performance Monitor allow you to add various counters to the Performance Monitor chart, which allows you to view counter statistics in real time. NetWare also provides the ability to view graphs of server performance using the Remote Manager.

  • Network usage and traffic can be monitored using network monitoring software such as protocol sniffers. For example, the Windows Network Monitor provides you with the ability to view network traffic and capture network frames generated on the network.

  • The ipconfig command can be executed from the command line to view the IP configuration of a Windows computer. Other commands, such as ping and traceroute , can be used with a number of different operating systems to check the connection between two network devices or the route that data takes when moving from a sending to a receiving device on the network.

  • Cable connection problems can be checked with devices such as voltmeters and time domain reflectometers.

  • Troubleshooting requires good documentation and a logical approach to problem solving.

Absolute Beginner's Guide to Networking
Absolute Beginners Guide to Networking (4th Edition)
ISBN: 0789729113
EAN: 2147483647
Year: 2002
Pages: 188
Authors: Joe Habraken © 2008-2017.
If you may any questions please contact us: