Re: [v6ops] DAD again [was: draft-ietf-v6ops-host-addr-availability discussion]

Gert Doering <> Sat, 14 November 2015 19:27 UTC

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Date: Sat, 14 Nov 2015 20:27:40 +0100
From: Gert Doering <>
To: "Hemant Singh \(shemant\)" <>
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Subject: Re: [v6ops] DAD again [was: draft-ietf-v6ops-host-addr-availability discussion]
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On Sat, Nov 14, 2015 at 07:14:28PM +0000, Hemant Singh (shemant) wrote:
> I will be out for next few hours.  I will reply to any mails after that.   I don't have any issue to disable DAD for  a lo interface.  Jinmei wants due diligence because rfc4862 is being changed and the 6man WG has to take a look.  The draft is not just a v6ops issue any more.   I also have another issue in that if DAD is disabled, what else makes sense to disable on the lo interface so that the interface has even more reduced processing to deal with. 

You do not need to disable DAD on lo.  Do it all you want.

But don't do DAD for interface A address on interface B.  This is the point
everybody has been making.

So, if you have an address on lo, there is no reason to do DAD for that
on eth0, eth1, pos3/4, or anything else in your box - as you wouldn't
do DAD for the eth0 address on eth1.

Unrelated interfaces.

And on lo0, there is no other party to conflict with, so do DAD if you 
want, or do not do DAD.  Nobody cares.

Gert Doering
        -- NetMaster
have you enabled IPv6 on something today...?

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