
6-196
Cisco Broadband Cable Command Reference Guide
OL-1581-07
Chapter 6 Cable CPE Commands
debug cable-modem mac messages
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
*Mar 7 01:44:06: MAC MANAGEMENT MESSAGE HEADER
*Mar 7 01:44:06: DA - 01E0.2F00.0001
*Mar 7 01:44:06: SA - 00E0.1EA5.BB60
Release
Modification
11.3(4)NA
This command was introduced for 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.