Re: [DNSOP] abandoning ANAME and standardizing CNAME at apex

Paul Wouters <paul@nohats.ca> Mon, 25 June 2018 16:44 UTC

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Date: Mon, 25 Jun 2018 12:44:07 -0400 (EDT)
From: Paul Wouters <paul@nohats.ca>
To: Tony Finch <dot@dotat.at>
cc: dnsop <dnsop@ietf.org>
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Subject: Re: [DNSOP] abandoning ANAME and standardizing CNAME at apex
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On Mon, 25 Jun 2018, Tony Finch wrote:

>> Then you might as well use that mechanism to update A/AAAA records and
>> skip the intermediate ANAME?
>
> ANAME will add two things beyond a provisioning-only setup:
>
> * a standard way to signal to dynamic auth servers where to get A/AAAA
>  records from

I understand, I just disagree this is the right way. I don't see why
this entire problem shouldn't be resolved at the well, resolver level.

> * a way to signal to recursives that they might get a better answer if
>  they query the target themselves

This you can do with ANAME records that are provisioned, and the only
modification needed would be to add ANAME to the additional/answer
section on auth servers. That's quite different from adding a protocol
requiring auth nameservers to interpret/fetch/verify/replace zone
records.

Paul