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Figure 12-9. Some tests return configuration information, whereas others produce a Passed or Failed response.

Figure 12-10. The IPAddress test pings the local computer to check for connectivity with your NIC, which is similar to typing ping localhost.

7Once you have reviewed the results, you can click the Save To File button and save the file for future reference. The file is automatically saved as an HTML file.

In addition to the standard diagnostic test that is performed, you can also customize the test by selecting Set Scanning Options in step 4. The option is also available at the

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end of each test you run, so you can modify your selections and run the diagnostics again. The options are listed under the headings Actions and Categories. The actions the test can perform include pinging, connecting, showing, saving to the desktop, and using a verbose (detailed) mode. Categories to test include Internet connections, computer information, and network protocols, as shown in Figure 12-11. Most of the items in this figure are selected by default, but notice that DNS, DHCP, default gateways, IP address, and WINS are not selected for the test. If you want to test these items as well, select their check boxes, and then clear any items that you do not want reported to you.

Figure 12-11. Select the actions and categories that you want to test.

Using Windows Support Tools

In addition to the tools installed by default in a Windows XP installation, Windows XP also includes another group of tools that you can install from the Windows XP installation CD. These support tools include a conglomeration of items developed for Microsoft Windows 2000 Professional and Microsoft Windows 2000 Server, so some of the tools apply more to Windows 2000 Server tasks rather than Windows XP tasks. However, there are a few networking tools in this group that you might want to use. To install the Windows Support Tools, follow these steps:

1Insert the Windows XP installation CD into the computer’s CD-ROM drive.

2When the Welcome To Microsoft Windows XP window appears, select Perform Additional Tasks.

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note If the CD’s installation program window and type d:\setup.exe

doesn’t automatically start up, open a Command Prompt , where d is the drive letter of your CD drive.

3Select Browse This CD to display a directory of the CD.

4Open the Support folder, and then open the Tools folder.

5Double-click Setup.exe to open the Windows Support Tools Setup Wizard.

6Follow the instructions in the wizard to complete the installation. Select Complete when prompted for the installation type so you won’t need to run the wizard again to install additional tools.

After the tools are installed, choose Start, All Programs, and point to Windows Support Tools. Because these tools are command-line utilities, they aren’t individually listed. Instead, open a Command Prompt window from the submenu that appears and read the Release Notes and Support Tools Help to learn the names and functions of the support tools. If you choose Support Tools Help and click the Alphabetical List Of Tools link, you’ll see that there are nearly 50 utilities available to you. Two of these utilities are discussed in the following sections.

Network Connectivity Tester (NetDiag.exe)

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The NetDiag tool is a command-line diagnostic tool that can help you locate networking problems and connectivity problems. The NetDiag tool performs a series of steps to test the functionality of the network components. It can provide a lot of information, and it is rather easy to use.

At the command prompt, type netdiag and press Enter. As partially shown in Figure 12-12, a long list of tests are run, data is gathered from those tests, and the results of the tests (Passed, Skipped, Failed) are reported.

note If you installed the support tools but NetDiag won’t run in a Command Prompt window, it’s probably because the folder for the support tools isn’t in the Windows XP search path. To avoid this problem, choose Start, All Programs, Windows Support Tools, Command Prompt. This will open a Command Prompt window set to the folder in which the support tools were installed, which will enable them to be located.

You can then read through the test and look for the information you’re interested in. Some of the more helpful tests include the following:

●Adapter: Local Area Connections information and tests

●Default Gateway Test

●DNS tests

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●Domain Membership Test

●IP Loopback Ping Test

●Modem Diagnostics Test

●IP Security Test

NetDiag also includes a few additional command-line options to control the test output. The most useful options are listed in Table 12-5. To see a complete list of switches as well as a complete list of the tests that are performed by NetDiag, type netdiag /? at the command prompt.

Figure 12-12. The NetDiag tool performs a number of network status and connectivity tests.

Table 12-5. NetDiag Switch Options

Option	Action
/q	This switch runs NetDiag in quiet mode. The output of the com-
	mand lists only the errors.
/v	Verbose output. This option displays all the results.
/l	This option logs the NetDiag output to Netdiag.log
/debug	This switch uses debugging mode, which provides an even
	greater amount of output. Use this only when trying to trouble-
	shoot specific problems because much of this output is only
	decipherable by network programming experts.
/fix	This switch fixes trivial problems that are found.

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Network Monitor Capture Utility (NetCap.exe)

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NetCap is a network monitor capture utility that captures data frames, or packets, entering and leaving a computer. The data collected is then saved to a log file where you or other network support personnel can analyze it in hopes of solving problems that might be occurring.

NetCap is a rather involved tool and is most often used by network administrators to look for specific network problems. You can capture network frames by typing netcap at the command prompt. The frames are continually captured until you press the Spacebar to stop the capture. If you type netcap /?, a long list of options appears. You can define filters for the Network Monitor driver so that you can choose the type of data that you want to monitor. To learn more, read Support Tools Help by choosing Start, All Programs, Windows Support Tools.

What Is Found in a Data Frame?

NetCap is a program that captures network frames (also known as packets) and records the data in a log file. Because these programs are used to hunt down difficult to trace problems on a network, they are often called packet sniffing or frame sniffing programs. So, what can be found by sniffing frames? Each data frame on a network contains information that can be useful to network administrators. By analyzing the frames, you can learn more about the kind of traffic that is running on the network and determine if any problems exist. Each data frame contains:

●Control information

●Source and destination addresses

●Protocol information

●Error-checking data

●The actual data being sent

Using NetCap, you can capture this information to analyze your network. For example, if your network is running slowly, you can use NetCap to sniff frames for a period of time, and then view those frames in a log file. Suppose you find a lot of broadcast frames that are congesting the network. You can read the destination address to find out which computer is sending out broadcast packets. You can then take steps to solve the broadcast problem on that particular computer or at least investigate whether or not the broadcast traffic is necessary.

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Finding Helpful Utilities on the Internet

If the many tools included in Windows XP and the Windows XP Support Tools don’t keep you busy, there are also many third-party tools available for network problem solving. The selections range from commercial applications to shareware and freeware applications. Many of these programs have trial versions that you can download from the Internet to see if they fit your needs. This section highlights a few of the many Internet utilities you will find.

Ping Plotter

Ping Plotter is a trace route tool that provides you with the same standard information that Tracert does, but it presents the information to you in a graphical format and includes additional features. The cool thing about Ping Plotter is that you can see a graphic of the trace and automatically repeat the trace at intervals you specify. For example, if your network or Internet connection slows down during certain times of the day, you can set Ping Plotter to run at those intervals and record the data for analysis. This is a great way to show your ISP when problems are occurring and exactly what routers are dropping packets. ISPs can then work to fix faulty routers or route traffic around them.

Besides its basic use of tracing a route, you can also use Ping Plotter to:

●Save the graphs and charts. You can even set up automatic saving.

●Watch routes and keep track of any route changes.

●Repeatedly trace a route and examine graphs of the minimum, maximum, and average values of each router’s performance.

●Configure alerts that will notify you when certain conditions occur. Alerts can even be configured to be sent to you via e-mail messages.

At the time of this writing, Ping Plotter is available as shareware or as a freeware product. The freeware product does not include all of the features that are available in the shareware product. You can download the shareware version and use it for 30 days before you have to pay for it. Be sure to try the shareware version first (the fee is only $15 to register it). It includes graphing features that provide more information than traditional text output, which makes it easier to troubleshoot the tracing process. You’ll find Ping Plotter at www.pingplotter.com. Figure 12-13 on the next page shows a typical trace display from the tool.

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Figure 12-13. Ping Plotter performs trace route functions in a graphical format.

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VisualRoute

Another utility displays geographic maps of its trace routes. VisualRoute, available in a trial version from www.visualroute.com, traces any URL or e-mail address (to the e-mail server) and displays the route for you on a world map. This is a fun tool, but it can also be very helpful in obtaining a graphical view of traffic patterns and access over the Internet. As shown in Figure 12-14, VisualRoute provides a simple interface where you can route Internet addresses, IP addresses, or e-mail addresses.

NetPerSec

NetPerSec is a utility that gives you the real-time speed of your Internet or network connection. You can see how many bytes of data your computer has sent and received, and you can view the data in a chart format for easy analysis. NetPerSec is a free download from www.pcmag.com, and it’s a good tool to have around.

NetPerSec is mainly touted as a utility that keeps track of your Internet speed, but it can help you see the amount of traffic flowing in and out of your computer on the LAN. If traffic seems to be moving slowly on the network, you can use this tool to view what might be happening. If you have more than one NIC, the Options tab of the application lets you choose which NIC to monitor. You can also choose to only monitor a dial-up connection or all network activity combined. By choosing the network traffic you want to monitor, you can gain insight into how data is flowing through your computer. Figure 12-15 shows the NetPerSec interface.

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Figure 12-14. VisualRoute displays the same information as other ping utilities but adds a mapping feature that includes additional information.

Figure 12-15. Use NetPerSec to see the speed of Internet and network connections in numerical and graphical formats—all in real time.

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Troubleshooting Network Connections

Troubleshooting is a process—a system of eliminating possible causes of problems until you discover the actual cause. That sounds easy enough, but if you have ever tried to solve computer problems, you know that the troubleshooting process can be complicated and difficult. The same is true when troubleshooting network connections. However, if you use the tools explored in this chapter, you are much more likely to find the cause of the problem quickly. The rest of this chapter details a basic approach to troubleshooting network connections, which is then applied to a few problems you might encounter. Remember that if your problem is not specifically described in this section, you can still apply the principles of troubleshooting to solve your particular problem.

A Philosophy of Troubleshooting

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Network users and administrators develop their own philosophy of troubleshooting. This philosophy often comes from years of trial and error, or it comes from books like this. Depending on your perspective, the way you troubleshoot computer problems will vary, but the following is a time-tested approach to troubleshooting you can apply to troubleshooting network connections or another problem with Windows XP.

●Stop. When the problem first occurs, don’t do anything but stop and think. Grab a notebook and write down exactly what happened when the problem occurred. Then think about what you were doing just before the problem occurred. For intermittent problems, this approach can help you isolate the problem, which will help you find the cure for it. The act of taking notes might seem trivial, but if the problem takes several hours to solve, you’ll be surprised at how convoluted your memory can become during that time!

●Plan. Before you attempt to solve the problem, look at your notes and think about the possible solutions to the problem. Many users who end up calling for technical support start out with a minor problem that they try to fix on their own by making random configuration changes. By the time they call for support, the minor problem has become a major one because of the additional complications caused by making changes haphazardly! Don’t end up in this predicament—take a logical look at the problem and make a plan that might lead to a solution.

●Act. Once you have documented the problem and have sketched out a plan for solving it, try to solve the problem using the most likely tool or the most likely solution. If the problem is fixed, you are home free. If the problem is not fixed, write down what you tried to do before moving on to the next possible solution. If you cannot solve the problem and must get help, this list of actions you have documented can be very helpful to technical support personnel. Help yourself by keeping records of your troubleshooting actions!

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●Get help. Make sure you check references that might help you, including this book and Microsoft Windows XP Inside Out by Ed Bott and Carl Siechert (Microsoft Press, 2001) for possible causes and solutions. A more technical but very comprehensive title is Microsoft Windows XP Professional Resource Kit Documentation (Microsoft Press, 2001). Don’t forget to use the Internet to search for solutions. The Microsoft Web site at www.microsoft.com has a comprehensive Search link to search hundreds of documents about different issues. Newsgroups accessed through Microsoft Outlook Express or another newsreader provide hundreds of groups dedicated to software and hardware issues with thousands of people helping each other solve computer problems. You’ll often find others with your specific problem, sometimes before the problem is documented in more official places. If you’re still unable to solve the problem, open the Windows XP Help And Support Center for help from Microsoft (choose Help And Support from the Start menu). Then click the Get Support Or Find Information In Windows XP Newsgroups link. Under Support, click the Get Help From Microsoft link. The Microsoft Online Assisted Support Wizard will guide you through the support process.

Solving Common Network Connection Problems

A few of the more common network connectivity problems and their solutions are discussed in the following sections. Remember that if your problem isn’t covered, the procedures described can often be applied to other problems as well.

Your Computer Cannot Connect to a Network

If your computer cannot connect to the network, follow these steps to troubleshoot the problem:

1Check your NIC and the cable. Make sure the NIC is installed and working (use Device Manager in the System Properties dialog box in Control Panel), and make sure the cable is plugged into the NIC. If the NIC is installed, you’ll see an icon for it in Network Connections. If the cable is unplugged, the icon will appear with a red X over it.

2If the NIC is plugged in and seems to be working, use Ping to ping the loopback address and then other hosts on your network.

3If the loopback test works but you cannot access other hosts, check your IP address and subnet mask against other hosts on the same subnet. You must use an IP address in the same range and the correct subnet mask to communicate with other computers on the network. If this information does not appear to be correct, run the Network Setup Wizard again, or manually configure the TCP/IP settings if required. You can let Windows XP try to repair the problem by right-clicking the LAN connection icon in Network Connections and choosing Repair.

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