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Cisco Broadband Cable Command Reference Guide
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Chapter 3 Cisco CMTS Show Commands
show cable modem
Tip
You can also specify the MAC address or IP address for a CPE device, and the Cisco CMTS will display
the information for the CM that is associated with that CPE device in its internal database.
Operation with Hot Standby Connection-to-Connection Protocol (HCCP) Configuration
If you are using Hot Standby Connection-to-Connection Protocol (HCCP) 1+1 or 1:n (N+1) redundancy,
the new primary processor after a switchover automatically creates a new database of the online cable
modems. This means that the
show cable modem
ip-address
command might not show a particular cable
modem until the CMTS receives IP traffic from that cable modem. You can force IP traffic by using the
ping
ip-address
command, and then the
show cable modem
ip-address
command will show the cable
modem. You can also display any particular cable modem by using the
show cable modem | include
ip-
address
command.
In addition, when HCCP redundancy has been configured, the Cisco IOS software automatically
synchronizes the secondary, backup cards whenever the configuration is changed. The cards can also be
synchronized manually, using the
hccp resync
command. When a SYNC event command is occurring,
CLI commands might be very slow to respond. In particular, if you enter the
show cable modem
command at the same time a SYNC event is occurring, the command might respond produce a blank
display, or it might display an error message similar to the following:
%No response from slot 6/1. Command aborted
If this occurs, wait a minute or so and retry the command.
Operation of the show cable modem Commands with Different Cable Interface Line Cards
The
show cable modem
commands display the most current information for standard cable interface
line cards, such as the Cisco uBR-MC16C, Cisco uBR-MC16S, and Cisco uBR-MC28C cards. If the
card itself is down, the
show cable modem
commands still show whatever information is appropriate
(such as offline cable modems and flap list information).
The
show cable modem
commands function slightly differently when used on routers that are using
Broadband Processing Engine (BPE) cable interface line cards (such as the Cisco uBR-MC16U/X,
Cisco uBR-MC28U/X, or Cisco uBR-MC5X20S/U). When BPE cards are the only cable interface cards
installed, the
show cable modem
commands do not display any output until at least one BPE card is up
and communicating with the router processor. If the BPE cards are not yet up, the
show cable modem
command does not display any output.
Additional show cable modem Commands
Other forms of the
show cable modem
command display additional information about CMs and their
current status. See the following commands for more details:
•
show cable modem access-group
—Displays information about the access group for each CM.
•
show cable modem classifiers
—Displays information about the classifiers being used for each CM.
•
show cable modem cnr
—Displays carrier-to-noise ratio (CNR) information for CMs that are using
cable interface line cards with hardware spectrum-management capabilities.
•
show cable modem connectivity
—Displays connectivity information for each CM.
•
show cable modem counters
—Displays traffic counters for each CM.
•
show cable modem cpe
—Displays information about the CPE devices using each CM.
•
show cable modem errors
—Displays packet error information for each CM.
•
show cable modem flap
—Displays flap-list information for each CM.