TROUBLESHOOTING

Checking a TCP/IP network pathway
If checking name resolution did not solve the problem, check each network pathway. Be sure to record the information you gather.

Using the Trace Route utility
Use the TRACERT command to determine what network pathway lies between the source and destination systems. This command determines the route from one host to another through the network, and displays an ordered list of the routers in the path with the IP addresses of the near-side interface of the routers.

Note A dedicated Trace Route utility may not be available on all platforms, and your firewalls are most likely blocking the ICMP sub-protocol of IP. Consult the site administrator to see if there is an equivalent for your platform.

To use TRACERT, type the following at the prompt:


Where -d tells the command not to resolve addresses to host names.

For example, the results of the TRACERT command might look like this:


In this example, there are two IP routers between the workstation and the server (three, minus the first one which reported itself, leaving two).

Checking the Maximum Transmission Unit (MTU)
Each end-node system and router port on the network has the ability to control the size of the TCP/IP packet. Each NIC (port) can have its MTU set to a different value, and each topology has a different default value. The network administrator can increase or decrease this setting to meet the requirements of the network. MTU traffic issues are handled at the TCP/IP level and not within IBM® Lotus® Notes® workstations or IBM® Lotus® Domino™ servers.

If any of the following situations exist, suspect an MTU problem, and contact your network administrator:

See also