Cisco Systems uBR7200 Series

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Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide

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Chapter4 Troubleshooting the System Managing Cable Modems on the HFC Network

To configure per modem filters, use the following commands in cable interface configuration mode.

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. A

typical registration and login procedure is shown below:

1. The CM registers with the Cisco uBR7200 series.

2. The Cisco uBR7200 series sends traps to management systems in use for the network.

3. The management system sets per modem filters using SNMP orrsh.

4. The user logs in at the server.

5. The login server obtains required modem and CPE information from the Cisco uBR7200 series.

6. The login serversets per-CPE filter in the Cisco uBR7200 series. The per-CPE filter overrides the

per modem filter settings.

7. If the CM goes offline for a brief period of time, filters defined using the Cisco uBR7200 series

remain active. If a CM stays offline for more than 24 hours, filter settings are reset.

8. Ifthe 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.

Table4-6 Instructions to Conﬁgure Per Modem Filters

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

receivedfrom cable modems and/or individual hosts

arefiltered based on the cable modem or the host the

packets are receivedfrom. 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. Themacaddr 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

toan access list. This defines the per-CM or per-host

filterrequirements implemented at the CMTS, rather

than at the CM. Access list numbers are 1 to 99 for

fastIP access lists, 100 to 199 for show extended IP

access lists.

Note Access list numbers of 700 to

799 do not apply.