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Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide
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Chapter4 Troubleshooting the System
Managing the Cisco uBR7246 VXR Clock Card

Debug Upstream Channel Description (UCD) Messages

This command activates debugging of upstream channel descriptor (UCD) messages. UCD messages
contain information about upstream channel characteristics and are sent to the cable modems on the
HFC network. Cable modems that are configured to use enhanced upstream channels use these UCD
messagesto identify and select an enhanced upstream channel to use. When this command is activated,
messages related to upstream channel descriptors are displayed on the Cisco uBR7200 series console.
The format for the command is as follows:
CMTS01# debug cable ucd
To deactivate debugging of cable upstream channel descriptor, use the following command:
CMTS01# no debug cable ucd
Managing the Cisco uBR7246 VXR Clock Card
Cisco IOS Release 12.1(1a)T1 introduced clock card commands that included:
•cable clock clear-counters
•cable clock force
•cable clock source-midplane
•show cable clock
•show controllers clock-reference
Cisco IOS Release 12.1(1a)T1 modified commands to support clock card operation include:
•show diag
•show frame-clocks
•show tech support
•show version

Clear Clock Counters

Toreset the counters that are displayed with the show controllers clock-reference command, use the
cable clock clear-counters privileged EXEC command.
cable clock clear-counters
This command resets any counters that were displayed from the last time the show controllers
clock-reference command was used.