3.5. Troubleshooting TCP/IP

When TCP/IP works well, life is good. Occasionally, however, TCP/IP connections will fail and you will need to determine the cause of the problem. Windows Server 2008 includes a handful of TCP/IP utilities you can use to test connectivity and troubleshoot connections. This section of the chapter examines TCP/IP troubleshooting in general and the tools included with Windows Server 2008 for that purpose.

3.5.1. Common troubleshooting concepts

As is the case when troubleshooting any problem, the first thing to consider when troubleshooting TCP/IP connections is whether anything has changed in the system's configuration. Problems with a newly installed computer typically point to an invalid IP address, a wrong subnet mask, or an incorrect default gateway. If TCP/IP has never worked on the system, open the TCP/IP properties for the connection and verify that they are correct.