Cisco Systems UBR924 manual Display the Cisco uBR924’s MAC Log File

Step 3—Display the Cisco uBR924’s MAC Log File

Step 3—Display the Cisco uBR924’s MAC Log File

A MAC-layer circular log file is stored inside the Cisco uBR924. This file contains a history of the log messages such as state event activities and timestamps. This is the most valuable information for troubleshooting the cable interface.

The MAC log file is displayed by entering the show controllers cable-modem 0 mac log command from privileged EXEC mode.

The most useful display fields in this log file are the reported state changes. These fields are preceded by the message CMAC_LOG_STATE_CHANGE. These fields show how the Cisco uBR924 progresses through the various processes involved in establishing communication and registration with the CMTS. The maintenance_state is the normal operational state; the wait_for_link_up_state is the normal state when the interface is shut down.

Note Because the MAC log file only holds a snapshot of 1023 entries at a time, you should try to display the Cisco uBR924’s log file within 5 minutes after the reset or problem occurs.

The following is the normal progression of states as displayed by the MAC log:

wait_for_link_up_state

ds_channel_scanning_state wait_ucd_state wait_map_state ranging_1_state ranging_2_state dhcp_state establish_tod_state security_association_state configuration_file_state registration_state establish_privacy_state maintenance_state

Note To translate this output into more meaningful information, see “Step 4—Interpret the MAC Log File and Take Action” on page 13.

Following is an example of what the MAC log file looks like when the Cisco uBR924 interface successfully comes up and registers with the CMTS. The output you see is directly related to the messages that are exchanged between the Cisco uBR924 and the headend CMTS.

uBR924# show controllers cable-modem 0 mac log
508144.340	CMAC_LOG_DRIVER_INIT_IDB_RESET	0x08098FEA
508144.342	CMAC_LOG_LINK_DOWN
508144.344	CMAC_LOG_LINK_UP
508144.348	CMAC_LOG_STATE_CHANGE	ds_channel_scanning_state
508144.350	CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND	88/453000000/855000000/6000000
508144.354	CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND	89/93000000/105000000/6000000
508144.356	CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND	90/111250000/117250000/6000000
508144.360	CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND	91/231012500/327012500/6000000
508144.362	CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND	92/333015000/333015000/6000000
508144.366	CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND	93/339012500/399012500/6000000
508144.370	CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND	94/405000000/447000000/6000000
508144.372	CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND	95/123015000/129015000/6000000
508144.376	CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND	96/135012500/135012500/6000000
508144.380	CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND	97/141000000/171000000/6000000
508144.382	CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND	98/219000000/225000000/6000000
508144.386	CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND	99/177000000/213000000/6000000

Troubleshooting Tips for the Cisco uBR924 Cable Access Router 11