Provider standard ARP Timeout?

Saku Ytti saku at
Fri Aug 10 10:27:39 CDT 2012

On (2012-08-10 10:23 -0400), Jay Nakamura wrote:

> Cisco default ARP timeout is 4 hours.  Do anyone change that to
> something shorter in a provider environment for customer with Ethernet
> connectivity?  What is a good value to set it to?

Maximum value should be your L2 MAC timeout. Most other vendors use low
limits these days (linux, junos come to mind).
So 300s max really.

If ARP timeout is higher than L2 MAC timeout you can cause loops in
otherwise correctly configured network.


More information about the NANOG mailing list