Troubleshooting guide

3. Troubleshooting Functional Failures During Operation
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Figure 3-6: Failure analysis procedure when IPv4 communication is not possible
(1) Checking the log
One probable cause of disabled communication is a line failure (or damage). To display the
messages that indicate a hardware failure, carry out the procedure below. You can find these
messages in the log displayed by the Switch.
For details about the contents of the log, see the manual Message and Log Reference.
1. Log in to the Switch.
2. Use the
show logging command to display the log.
3. Each entry in the log indicates the date and time that a failure occurred. Check whether a log
entry was displayed for the date and time when communication was disabled.
4. For details about the failure and corrective action for the log entry described above, see the
manual Message and Log Reference, and then follow the instructions given in the manual.