Cisco Systems uBR7200 manual Configuring DHCP Options, Activating Cable Proxy ARP Requests, MC-576

Configuring Headend Broadband Access Router Features

Configuring DHCP Options

Activating Cable Proxy ARP Requests

To activate cable proxy ARP for host-to-host communications, use the following command in cable interface configuration mode:

Command	Purpose
CMTS01(config-if)# cable proxy-arp	Enables proxy ARP on the cable interface. This is
	the default.

Verifying Cable Proxy ARP Requests

To verify whether or not cable proxy ARP has been activated or deactivated, enter the more system:running-configcommand and look for the cable interface configuration information. If cable proxy ARP has been activated, it does not appear in the output. If cable proxy ARP has been deactivated, it appears in the output as no cable proxy-arpas shown in this command output excerpt:

CMTS01# more system:running-config

Building configuration...

Current configuration:

!

interface Cable6/0

ip address 1.1.1.1 255.255.255.0 no keepalive

no cable proxy-arp

cable insertion-interval 150000 cable downstream annex B

cable downstream modulation 64qam cable downstream interleave-depth 32 cable downstream symbol-rate 5056941 cable upstream 0 frequency 15008000 cable upstream 0 fec

cable upstream 0 scrambler no cable upstream 0 shutdown

Troubleshooting Tips

To troubleshoot the configuration, make sure you entered the correct port and cable modem card slot number when you activated cable proxy ARP.

Configuring DHCP Options

The following sections describe configurable DHCP options for the Cisco uBR7200 series.

Activating Cable Relay Agent

The cable relay agent is for use with DOCSIS-based DHCP servers that use option 87 to automatically map the Ethernet MAC address of a host (end user PC) with the cable modem to which it is connected.

Cisco IOS Multiservice Applications Configuration Guide

MC-576