Re: [Asrg] Fallback to MX

John Levine <> Fri, 12 February 2010 15:14 UTC

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Date: 12 Feb 2010 15:15:27 -0000
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From: John Levine <>
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Subject: Re: [Asrg] Fallback to MX
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>> There is no chance whatsoever that the RFC standards will change.
>Ever? Even if it became common practice? I guess that the standards process 
>isn't going to lead on this question.

Really, I know the people involved, and remember that I feel the same
way you do about fallback from MX to AAAA.

>I've never had any complaints, and I will ensure when we do deploy IPv6, I 
>don't permit email from domains that have AAAA but not A or MX records.

I have a theory that you will never, ever, have any reason to accept mail
from IPv6 networks, since everyone you want to hear from will have an
MTA or gateway on IPv4, but that is a separate argument.