Cisco UBR904 Troubleshooting Guide - Page 31

show controllers cable-modem mac show controllers cable-modem mac To show detailed MAC-layer information for a cable modem, enter the show controllers cable-modem mac command in privileged EXEC mode. show controllers cable-modem number mac [errors | hardware | log | resets | state] Syntax Description number errors hardware log resets state The controller number inside the cable modem. (Optional) Displays a log of the error events that are reported to SNMP. This keyword gives you a way of looking at the error events without using a MIB. (Optional) Displays all MAC hardware registers. (Optional) Displays a history of MAC log messages, up to 1023 entries. This is the same output that is displayed when the debug cable-modem mac log command is entered. (Optional) Extracts all the reset causes out of the MAC log file and summarizes them into a mini report. (Optional) Displays a summary of the MAC state. Command Mode Privileged EXEC Usage Guidelines This command first appeared in Cisco IOS Release 11.3 NA. MAC log messages are written to a circular log file even when debugging is not turned on. These messages include timestamps, events, and information pertinent to these events. Enter the show controllers cable-modem mac log command to view MAC log messages. If the cable modem interface fails to come up or resets periodically, the MAC log will capture what happened. For example, if an address is not obtained from the DHCP server, an error is logged, initialization starts over, and the cable modem scans for a downstream frequency. The most useful keywords for troubleshooting a cable modem are log, errors, and resets. See Example 1, Example 2, and Example 3. Troubleshooting Tips for the Cisco uBR904 Cable Modem 31