[119221] in North American Network Operators' Group
Re: about interdomain multipath routing.
daemon@ATHENA.MIT.EDU (Steven King)
Mon Nov 9 23:26:01 2009
Date: Mon, 09 Nov 2009 23:22:23 -0500
From: Steven King <sking@kingrst.com>
To: Jack Bates <jbates@brightok.net>
In-Reply-To: <4AF8E926.1010004@brightok.net>
Cc: Bin Dai <bin.danieldai@gmail.com>, nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
Those are very good points Jack. We stopped using multihop for those
same reasons.
Jack Bates wrote:
> Matthew Petach wrote:
>>
>> I've outlawed the use of multihop eBGP for load-sharing here; when we
>> get
>> multiple links off the same router to a peer or upstream, they are
>> configured
>> with multipath. We've got hundreds of BGP sessions across the network
>> configured with multipath on them.
>>
>
> Same here for my connections, though some of my customers are stuck
> with multihop eBGP in certain remote areas, but that's a completely
> different scenario (single link, but obsolete equipment) and out of my
> control.
>
> I much prefer multipath, especially given that the standard multihop
> config uses static routing and there are conditions that could cause
> the flap of the eBGP session during a single link outage. With
> Multipath, only the effected path goes down, as it should.
>
>
> Jack
>
--
Steve King
Network Engineer - Liquid Web, Inc.
Cisco Certified Network Associate
CompTIA Linux+ Certified Professional
CompTIA A+ Certified Professional
