Gratuitous ARP Packets over Routers

[dantoine]

WE are testing a CCX compliant device on a stand alone network, what we see from looking at the ARP debug is the Router is not responding to the Devices Gratuitous ARPs, are they filtered out or blocked?

We are running a Cisco 2600 series router with IOS 12.3(9c)

Regards Deyon Antoine

[Richard Burts]

What kind of response are you expecting?

The gratuitous ARP is an announcement: I am on the network, here is my MAC and my IP. I am not aware that any response is expected to gratuitous ARP.

Are there other problems, or other symptoms that indicate problems?

If it were a regular ARP rather than a gratiutous ARP there are several things that might prevent responses. These would include, is it a proper source address (within the subnet defined on the router interface), if the destination is not in the local subnet is proxy arp enabled, does the router have a proper route toward the remote destination, etc.

If you give more description of what is happening we may be able to help more.

HTH

Rick