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Re: [DNSOP] What should ANAME-aware servers do when target records are verifiably missing?

Tony Finch <dot@dotat.at> Fri, 12 April 2019 11:05 UTC

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Date: Fri, 12 Apr 2019 12:05:24 +0100
From: Tony Finch <dot@dotat.at>
To: Matthew Pounsett <matt@conundrum.com>
cc: Richard Gibson <richard.j.gibson@oracle.com>, Bob Harold <rharolde@umich.edu>, dnsop <dnsop@ietf.org>
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Subject: Re: [DNSOP] What should ANAME-aware servers do when target records are verifiably missing?
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Matthew Pounsett <matt@conundrum.com> wrote:
>
> I feel like this is creating an even bigger potential problem.  What
> happens when the owner of the ANAME target legitimately wants that
> name to go away, but some other zone owner is leaving an ANAME in
> place pointing to that now-nonexistent name?  Continuing to serve the
> sibling records indefinitely seems like serve-stale gone horribly
> wrong.

It's worth noting that Oracle's ANAME model does not couple the sibling
addresses to the ANAME target addresses. As I understand it, they have
additional "fallback" infrastructure (web servers and whatnot) which is
used when the ANAME target isn't available.

I'm not sure how this would work as a replacement for CNAME, when the
request from the user comes without any information about how to set up a
fallback server.

Tony.
-- 
f.anthony.n.finch  <dot@dotat.at>  http://dotat.at/
Biscay: Variable 3 or less, becoming southeast 3 or 4. Moderate, becoming
slight. Fair. Moderate or good.

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