Installation guide

5-7
Cisco uBR7100 Series Universal Broadband Router Software Configuration Guide
OL-2238-03
Chapter 5 Troubleshooting the System
Managing Cable Modems on the HFC Network
Caution The system applies filters after the cable modem registers with the CMTS. Filter definitions are not saved
across system reboots and must be applied each time a CM registers.
The software supports traps to alert CMTS administrators on CMs going offline or back online. This is
a typical registration and login procedure:
1. The CM registers with the Cisco uBR7100 series CMTS.
2. The Cisco uBR7100 series CMTS sends traps to management systems in use for the network.
3. The management system sets per modem filters using SNMP or rsh.
4. The user logs in at the server.
5. The login server obtains required modem and CPE information from the Cisco uBR7100 series
CMTS.
6. The login server sets per-CPE filter in the Cisco uBR7100 series CMTS. The per-CPE filter
overrides the per modem filter settings.
7. If the CM goes offline for less than 24 hours, filters that have been defined using the Cisco uBR7100
series CMTS remain active. If a CM stays offline for more than 24 hours, the filter settings are reset.
8. If the user logs out or the login server detects that the user is not online, the login server sets default
filters for the CM or the CPE device.
Configuring the Maximum Number of Hosts Attached to a Cable Modem
To specify the maximum number of hosts that can be attached to a subscriber’s cable modem, use the
following command in cable interface configuration mode.
Command Purpose
CMTS01(config-if)# cable {modem |
host | device} {macaddr ipaddr |}
access group acl
Configure access lists to be specified on a per-interface and
per-direction basis. The packets received from cable modems
and individual hosts are filtered based on the cable modem or
the host the packets are received from. Use modem if the
device is a cable modem. Use host if the device is a CPE
device attached to a cable modem.
Define the filter to be applied to the device and a given
address. The macaddr specifies the cable modem’s or CPE
device’s unique MAC address.
Use the ipaddr option to specify the CM or CPE device’s
current IP address.
Use the acl option to assign the CM or CPE device to an
access list. This defines the per-CM or per-host filter
requirements implemented at the CMTS, rather than at the
CM. Access list numbers are 1 to 99 for fast IP access lists,
100 to 199 for show extended IP access lists.
Note Access list numbers of 700 to 799 do not apply.