IP Troubleshooting Procedures
The General approach of the process of troubleshooting TCP/IP connectivity issues with the assumption that you will have access to the client (or source) and may not have access to the server (or destination). If the problem is determined to be a server issue, you contact the server administrator. If you are the server administrator, you can apply the troubleshooting process in reverse (server to client) to further troubleshoot connectivity issues. To efficiently troubleshoot a TCP/IP connectivity problem, it is necessary to identify a single pair of source and destination devices that are exhibiting the connectivity problem. When you've selected the two devices, test to make sure that the problem is actually occurring between these two devices. Possible problems include these:
•Physical layer issue somewhere along the path
•First-hop Layer 3 connectivity issue, local LAN segment
•Layer 3 IP connectivity issue somewhere along the packet's path
•Name resolution issue
According to the cisco site, below are some starting points they suggest…. 1.Try to ping from the source to destination device by IP address. If the ping fails, verify that you are using the correct address, and try the ping again. If the ping still fails, go to the next section, "Troubleshooting Local Connectivity Problems." Otherwise, proceed to Step 2.
2.Try to ping from the source to the destination device by name. If the ping fails, verify that the name is correctly spelled and that it refers to the destination device, and then try the ping again. If the ping still fails, go to the section "Troubleshooting Domain Name Server Problems," later in this chapter. Otherwise, proceed to Step 3.
3.If you can ping the destination by both name and address, it appears that the problem is an upper-layer problem. Go to the section "Troubleshooting Upper Layer Problems," later in this chapter.
Another way to troubleshoot would be to use...