Specifications

DOCSIS 1.1 for Cisco uBR905 and Cisco uBR925 Cable Access Routers and Cisco CVA122 Cable Voice Adapters

Command Reference

Cisco IOS Release 12.2(15)CZ

Command Modes Privileged EXEC

Command History

Usage Guidelines The output from this command is very verbose, displaying the details of the DOCSIS MAC-layer

messages, and is usually not needed for normal interface debugging. The command is most useful when

attempting to attach a router to a CMTS that is not DOCSIS-qualified.

Caution This command should be used only while debugging CM operation. Displaying debugging messages

consumes system resources, and turning on too many messages could negatively affect system

performance.

Examples The following example shows typical output from the debug cable-modem mac messages command.

A separate command must be given for each message type to be displayed.

Much of the information, such as REG-REQ messages, is displayed in hexadecimal dump format, using

the Type/Length/Value (TLV) format required by the DOCSIS specification.

Note For complete descriptions of the MAC-layer management messages, see the DOCSIS Radio Frequency

Interface Specification (SP-RFIv1.1-I07-010829 or later), available from CableLabs at

http://www.cablemodem.com/specifications.html.

Router# debug cable mac messages ucd

ucd message debugging is on

Router# debug cable mac messages map

map message debugging is on

Router# debug cable mac messages rng-rsp

rng-rsp message debugging is on

Router#

*Mar 7 01:44:06:

*Mar 7 01:44:06: UCD MESSAGE

*Mar 7 01:44:06: -----------

*Mar 7 01:44:06: FRAME HEADER

*Mar 7 01:44:06: FC - 0xC2 == MAC Management

*Mar 7 01:44:06: MAC_PARM - 0x00

*Mar 7 01:44:06: LEN - 0xD3

Release Modifications

11.3(4)NA This command was introduced on the Cisco uBR904 cable access router.

12.0(4)XI1 Support was added for the Cisco uBR924 cable access router.

12.1(3)XL Support was added for the Cisco uBR905 cable access router.

12.1(5)XU1 Support was added for the Cisco CVA122 Cable Voice Adapter.

12.2(2)XA Support was added for the Cisco uBR925 cable access router.

12.2(15)CZ The dcc-ack, dcc-req, and dcc-rsp options were added to support

DOCSIS 1.1 operations.

12.3(2)T The up-dis option was supported.