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Re: [DNSOP] RFC 8482 (the ANY -> HINFO hack) and DNAME

Tony Finch <dot@dotat.at> Fri, 15 November 2019 13:26 UTC

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Date: Fri, 15 Nov 2019 13:26:39 +0000
From: Tony Finch <dot@dotat.at>
To: Shane Kerr <shane@time-travellers.org>
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Subject: Re: [DNSOP] RFC 8482 (the ANY -> HINFO hack) and DNAME
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Shane Kerr <shane@time-travellers.org> wrote:

> On the other hand, it seems unlikely that any resolver actually sends
> ANY queries to authoritative servers.

This happens when the resolver's cache doesn't have an entry for the name,
so the resolver sends the ANY query to the authoritative servers. It's
rare because ANY queries are rare, but it's easy to make it happen when
you want it to.

> We have chosen to perform CNAME synthesis for ANY queries that match a DNAME
> subtree, based on the logic that if CNAME is special when added by hand then
> it is probably also special when synthesized.

That's correct.

Tony.
-- 
f.anthony.n.finch  <dot@dotat.at>  http://dotat.at/
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