[31162] in North American Network Operators' Group

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RE: Confussion over multi-homing

daemon@ATHENA.MIT.EDU (Paul Froutan)
Thu Sep 14 17:12:20 2000

Message-Id: <4.2.2.20000914155312.04b8bf00@pop3.rackspace.com>
Date: Thu, 14 Sep 2000 16:09:09 -0500
To: Richard Welty <rwelty@vpnet.com>,
	Geoffrey Zinderdine <gzinderdine@home.com>
From: Paul Froutan <pfroutan@rackspace.com>
Cc: nanog@merit.edu
In-Reply-To: <F5EC0261691CD411887200E018C19DAC022A76@TROYNT01>
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Errors-To: owner-nanog-outgoing@merit.edu



At 9/14/00 -0400, Richard Welty wrote:

> > Wouldn't one of the ISPs have to advertise a longer prefix?
>
>actually, to do it right, both have to advertise the longer prefix --
>or more specifically, they have to both make holes in their filters
>permitting the multi-homed site to advertise them.
>
>this is what we're doing in our Troy, NY facility -- we have 2
>upstreams,
>and we have a /24 from one of them, which both of them pass through.

What you can do is get permission from the ISP that provides you the IPs 
(say ISP A) so you can have other ISPs announce your blocks.  You also need 
to get ISP A to deaggregate your block and announce it separately into the 
global BGP table.  We did this back in the day and it works fine if the ISP 
giving you IPs is somewhat reasonable and helpful.

----------------------------------------------------------------------
Paul Froutan                              Email: pfroutan@rackspace.com
Rackspace Managed Hosting                    <http://www.rackspace.com>



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