[187360] in North American Network Operators' Group
Re: IX ARP Timeout
daemon@ATHENA.MIT.EDU (sthaug@nethelp.no)
Thu Jan 28 02:06:16 2016
X-Original-To: nanog@nanog.org
Date: Thu, 28 Jan 2016 08:06:12 +0100 (CET)
To: nanog@ics-il.net
From: sthaug@nethelp.no
In-Reply-To: <662200281.11447.1453950132791.JavaMail.mhammett@ThunderFuck>
Cc: nanog@nanog.org
Errors-To: nanog-bounces@nanog.org
> So I'm looking at the policies, recommended configurations, etc. of other IXes. We try to model a lot of ourselves on what the Europeans do (even if we come up short in some areas). I was reading through the AMS-IX guide.
>
> https://ams-ix.net/technical/specifications-descriptions/config-guide#3.1
>
> They recommend a four hour ARP timeout. Thoughts? Seems a bit excessive, but I don't have over 700 networks on my IX. That said, I don't have over 700 members on my IX generating a ton of ARP traffic, so I'm probably fine recommending a smaller value.
As far as I know 4 hours has been the Cisco IOS default for many years.
So you'll find millions of routers around the world with that value. I
agree that it may be excessive in some situations.
Steinar Haug, Nethelp consulting, sthaug@nethelp.no
