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Re: DAD question

Karl Auer <kauer@biplane.com.au> Sat, 11 August 2012 21:39 UTC

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Message-ID: <1344721144.6453.29.camel@karl>
Subject: Re: DAD question
From: Karl Auer <kauer@biplane.com.au>
To: ipv6@ietf.org
Date: Sun, 12 Aug 2012 07:39:04 +1000
In-Reply-To: <20120811.180104.41668882.sthaug@nethelp.no>
References: <36AA0AF8-95FD-4751-AE2E-A7A3D07038EB@cisco.com> <409F28A1-7974-4524-893D-CEF349A96657@employees.org> <5FAE0128-DDE7-45C4-8632-F56EAA1BE362@gmail.com> <20120811.180104.41668882.sthaug@nethelp.no>
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On Sat, 2012-08-11 at 18:01 +0200, sthaug@nethelp.no wrote:
> Duplicate MAC addresses are regularly seen in the wild.

It's important to remember that DAD is link local. It is only checking
whether the same address occurs on the local link. Duplicate MAC
addresses are not actually a problem as long as the duplicates are not
on the same link. If the duplicates ARE on the same link, then you have
a real problem at layer 2 anyway. The same link local address, based on
a MAC, is also a real problem if it's duplicated, for much the same
reason.

Regards, K.

-- 
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Karl Auer (kauer@biplane.com.au)
http://www.biplane.com.au/kauer
http://www.biplane.com.au/blog

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