Tuesday, February 24, 2009

Local Proxy ARP - hmmm it's not ordinary ip proxy ARP

The local proxy ARP feature allows the Multilayer Switching Feature Card (MSFC) to respond to ARP requests for IP addresses within a subnet where normally no routing is required. With the local proxy ARP feature enabled, the MSFC responds to all ARP requests for IP addresses within the subnet and forwards all traffic between hosts in the subnet. Use this feature only on subnets where hosts are intentionally prevented from communicating directly to the Catalyst 6500 series switch on which they are connected.
Before the local proxy ARP feature can be used, the IP proxy ARP feature must be enabled. The IP proxy ARP feature is enabled by default.
Internet Control Message Protocol (ICMP) redirects are disabled on interfaces where the local proxy ARP feature is enabled.
Examples
The following example shows how to enable the local proxy ARP feature:
Router(config-if)# ip local-proxy-arp

Best Regards,
Deepak Arora

3 comments:

Unknown said...

difference between proxy-arp and local-proxy-arp ..kindly explain with an example

cisco said...

"ICMP redirects are disabled where local proxy-ARP is enabled" is true for all cisco IOS routers? If so, are there any workarounds to somehow allow local proxy-ARP to pull in the packets then route back out the same interface to another router which does not have local proxy-ARP enabled?

Ferzan Unlu said...

Great and concise article.