Chapter 10. Troubleshooting Connectivity

Objectives

4.1 Given a troubleshooting scenario, select the appropriate network utility from the following:

• tracert/traceroute

• ping

• arp

• netstat

• nbtstat

• ipconfig/ifconfig

• winipcfg

• nslookup/dig

4.2 Given output from a network diagnostic utility (for example, those utilities listed in objective 4.1), identify the utility and interpret the output

4.3 Given a network scenario, interpret visual indicators (for example, link LEDs [Light Emitting Diode] and collision LEDs [Light Emitting Diode]) to determine the nature of a stated problem

4.4 Given a troubleshooting scenario involving a client accessing remote network services, identify the cause of the problem (for example, file services, print services, authentication failure, protocol configuration, physical connectivity, and SOHO [Small Office/Home Office] router)

4.5 Given a troubleshooting scenario between a client and the following server environments, identify the cause of a stated problem:

• UNIX/Linux/Mac OS X Server

• Netware

• Windows

• Appleshare IP (Internet Protocol)

What you need to know

• Use various TCP/IP troubleshooting tools including ping, tracert, traceroute, arp, netstat, nbtstat, ipconfig, ifconfig, winipcfg, nslookup, and dig. Interpret the output from these tools.

• Interpret visual indicators such as LEDs on network devices to help troubleshoot connectivity problems.

• Understand the most common causes of remote connectivity issues, including troubleshooting of Internet access mechanisms such as Cable, DSL, and Dial-Up.

• Identify the cause and remedy for common network client connectivity issues such as authentication failure, permissions issues, and incorrect protocol configurations.