Re: [DNSOP] new ANAME draft: draft-hunt-dnsop-aname-00.txt

Tony Finch <dot@dotat.at> Tue, 11 April 2017 18:42 UTC

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Date: Tue, 11 Apr 2017 19:42:29 +0100
From: Tony Finch <dot@dotat.at>
To: Paul Wouters <paul@nohats.ca>
cc: dnsop <dnsop@ietf.org>
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Subject: Re: [DNSOP] new ANAME draft: draft-hunt-dnsop-aname-00.txt
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Paul Wouters <paul@nohats.ca> wrote:
>
> Can you give me an example of deploying ANAME outside the zone APEX that
> is not solved by allowing a CNAME to point to a CNAME (which most code I
> think already allows anyway)

https://www.ietf.org/mail-archive/web/dnsop/current/msg19909.html

If you have a subdomain that needs to be a mail domain and a web site, you
need an MX pointing at your mail server and address records pointing at
your web server. You can't use a CNAME because they are usually different
servers.

Also, mail domains cannot in practice be CNAMEs because of the disaster of
RFC 821 / RFC 1122 mail domain canonicalization.

Tony.
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