ARP / Cisco Router Wierdness

[Bill Moran]

Peter Pauly <ppauly at gmail.com> wrote:

> This morning while attempting to replace a server with a new machine
> (same IP address, the old machine was unplugged), The Cisco 2600
> router's arp table continued to point to the old DNS server's MAC
> address.
> 
> Even after rebooting the new server (Freebsd 5.2.1), the MAC address
> remained unchanged in the router. The router continued to point to the
> old machine's MAC address.
> 
> I updated the entry manually in the router and all was well. But I am
> concerned that Freebsd is not announcing it's MAC address when the
> machine or interface comes up. Any ideas?

I'm not an ARP expert, but isn't it the job of the device maintaining an
ARP table to properly time out and refresh the entries in that table?

I.e.  shouldn't you be posting this question to a Cisco mailing list,
asking why the 2600 didn't automatically pick up the new MAC address?

Corrections are welcome if I'm wrong on this count.

-- 
Bill Moran
Potential Technologies
http://www.potentialtech.com