Re: [DNSOP] ANAME precedence [issue #58]

Jan Včelák <jv@fcelda.cz> Tue, 30 April 2019 09:56 UTC

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Date: Tue, 30 Apr 2019 11:56:15 +0200
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Subject: Re: [DNSOP] ANAME precedence [issue #58]
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On Fri, Apr 26, 2019 at 8:30 PM 神明達哉 wrote:
> > Jan Včelák mentioned that at least NS1 uses a different order of
> > priority: If an sibling address record exists next to the ANAME it takes
> > precedence and no target lookup is done for that address record type.
>
> if there's a specific use case where this behavior is important,
> either the developer or user of this implementation should be able to
> clarify that.  At least until we know that I don't see the point of
> considering this choice.

The reason for different processing order in our implementation is
merely historical: ALIAS was intended to solve the problem with CNAME
in zone apex, our customers were familiar with CNAME processing, and
therefore we wanted ALIAS to resemble CNAME closely. CNAME is
practically a fallback record as well. I'm not aware of any specific
use case where such behavior would be required although it's possible
that our customers have developed some use case over the years.

It looks like there is an agreement that ANAME should take precedence
over A/AAAA. That's fine with me. We will figure it out for our
customers.

Jan