user manual

Configuring Headend Broadband Access Router Features
Activating Host-to-Host Communication (Proxy ARP)
MC-575
Cisco IOS Multiservice Applications Configuration Guide
Verifying ARP Requests
To verify whether or not cable ARP has been activated, enter the more system:running-config
command and look for the cable interface configuration information. If ARP has been activated, it does
not appear in this output. If ARP has been deactivated, it will appear in the output as
no cable arp
as 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 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 ARP and when you entered the show interface cable command.
Activating Host-to-Host Communication (Proxy ARP)
Cable proxy ARP allows the Cisco uBR7200 series to issue cable ARP requests on behalf of cable
modems on the same cable network subnet.
Note Because the downstream and upstreams are separate interfaces, modems cannot directly
perform ARP with other modems on the cable plant.
Note The default values for the commands used in this configuration task are adequate in most
cases to configure the Cisco uBR7200 series.