[168216] in North American Network Operators' Group
Re: best practice for advertising peering fabric routes
daemon@ATHENA.MIT.EDU (Niels Bakker)
Wed Jan 15 15:47:11 2014
Date: Wed, 15 Jan 2014 21:46:25 +0100
From: Niels Bakker <niels=nanog@bakker.net>
To: nanog@nanog.org
Mail-Followup-To: nanog@nanog.org
In-Reply-To: <30B98ADB-1CED-4022-9E80-576EEBF40697@bloomcounty.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
* clay@bloomcounty.org (Clay Fiske) [Wed 15 Jan 2014, 20:34 CET]:
>Semi-related tangent: Working in an IXP setting I have seen weird
>corner cases cause issues in conjunction with the IXP subnet
>existing in BGP. Say someone’s got proxy ARP enabled on their router
>(sadly, more common than it should be, and not just from noobs at
>startups). Now say your IXP is growing and you expand the subnet. No
>matter how much you harp on the customers to make the change, they
>don’t all do it at once. Someone announces the new, larger subnet in
>BGP. Now when anyone ARPs for IPs in the new part of the range,
>proxy ARP guy (still on the smaller subnet) says “hey I have a route
>for that, send it here”. That was fun to troubleshoot. :)
Proper run IXPs pay engineers to hunt down people with Proxy ARP
enabled on their peering interfaces.
-- Niels.
--
"It's amazing what people will do to get their name on the internet,
which is odd, because all you really need is a Blogspot account."
-- roy edroso, alicublog.blogspot.com
