Re: best practice for advertising peering fabric routes

[Niels Bakker <niels=nanog () bakker net>]

* 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