3. Troubleshooting Functional Failures in Operation1183.17 NTP Communication Failure3.17.1 Time Synchronization by NTP Is DisabledIf time synchronization by NTP is disabled, isolate the problem by following the failure analysis methods shown in thetable below.Table 3-65: NTP Failure Analysis MethodNo. Troubleshooting Steps and Command Action1 Execute the show clock command to see ifa time zone has been set up.If the command retrieves the time zone setting, go to No. 2.If no time zone has been set up in the output of the command, set up a time zone.2 Check the difference in time between thissystem and the NTP server.Go to No. 3 if the difference in time between this system and the NTP server iswithin 1000 seconds.If the difference in time between this system and the NTP server is greater than1000 seconds, adjust the time of this system with the time of the NTP server usingthe set clock command.3 Check communication with the NTP serverby IPv4.Execute the ping command to see if NTP server and this system cancommunicate over IPv4 protocol.Confirm that no setting for discarding packets using UDP port number 123 existsin the NTP server or this system.
