[155463] in North American Network Operators' Group
Re: Provider standard ARP Timeout?
daemon@ATHENA.MIT.EDU (Saku Ytti)
Fri Aug 10 11:28:36 2012
Date: Fri, 10 Aug 2012 18:27:39 +0300
From: Saku Ytti <saku@ytti.fi>
To: nanog@nanog.org
In-Reply-To: <CADs2+OG-vQMSze7g9wHMENnR99Xh4QTOPa0i37F00S3NBwAfMQ@mail.gmail.com>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
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.
--
++ytti
