When gathering symptoms for probable software configuration problems, a
troubleshooter should start at the last known point where the network
functioned correctly. If an end-user station can successfully ping the gateway
but not the DNS server on another network segment, then an entire set of
potential problems associated with the physical layer at the user-site can be
eliminated. Effective questioning techniques can discover this type of
information without requiring a trip to the end-user location. The commands
shown in the figure can be used to check the status of various devices and be
used to determine which configuration aspects to inspect.

The
troubleshooter should use effective questioning techniques to document the
symptoms of a problem:
- Ask questions that are pertinent to the problem.
- Use each question as a means to either eliminate or discover possible
problems.
- Speak at a technical level that the user can understand.
- Ask the user when the problem was first noticed.
- Ask the user to re-create the problem, if possible.
- Determine the sequence of events that took place before the problem
happened.
- Match the symptoms that the user describes with common problem causes.