Chapter 10: Network Troubleshooting

Overview

THE FOLLOWING NETWORK+ EXAM OBJECTIVES ARE COVERED IN THIS CHAPTER:

• 4.2 Given a troubleshooting scenario involving a small office/ home office network failure (e.g., xDSL, cable, home satellite, wireless, POTS), identify the cause of the failure.

• 4.3 Given a troubleshooting scenario involving a remote connectivity problem (e.g., authentication failure, protocol configuration, physical connectivity), identify the cause of the problem.

• 4.6 Given a network scenario, interpret visual indicators (e.g., link lights, collision lights, etc.) to determine the nature of the problem.

• 4.7 Given output from a diagnostic utility (e.g., tracert, ping, ipconfig, etc.), identify the utility and interpret the output.

• 4.9 Given a network problem scenario, select an appropriate course of action based on a general troubleshooting strategy. This strategy includes the following steps:

1. Establish symptoms.

2. Identify the affected area.

3. Establish what has changed.

4. Select the most probable cause.

5. Implement a solution.

6. Test the result.

7. Recognize the potential effects of the solution.

8. Document the solution.

• 4.10 Given a troubleshooting scenario involving a network with a particular physical topology (i.e., bus, star/hierarchical, mesh, ring, and wireless) and including a network diagram, identify the network area affected and the cause of the problem.

• 4.11 Given a network troubleshooting scenario involving a client connectivity problem (e.g., incorrect protocol/client software/authentication configuration, or insufficient rights/permissions), identify the cause of the problem.

• 4.12 Given a network troubleshooting scenario involving a wiring/infrastructure problem, identify the cause of the problem (e.g., bad media, interference, network hardware).

There is no doubt about it. The only way to get good at troubleshooting computers and networks is the same way to get good at any other art: practice, practice, practice. And as with any art, you must learn some basic skills before you can start practicing.

This chapter introduces you to some items to keep in mind when troubleshooting networks as well as the troubleshooting topics covered on the Network+ exam. In this chapter, we’ll examine some basic troubleshooting techniques. First, we’ll look at how to check quickly for simple problems. Then, we’ll discuss a common troubleshooting model that you can use to identify many network problems. Finally, we’ll look at some common troubleshooting resources, and tips and tricks that you can use to make troubleshooting easier. Let’s start with how you go about narrowing down the problem.