Re: [DNSOP] Fundamental ANAME problems

Tony Finch <dot@dotat.at> Tue, 06 November 2018 13:44 UTC

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Date: Tue, 6 Nov 2018 13:44:35 +0000
From: Tony Finch <dot@dotat.at>
To: Joe Abley <jabley@hopcount.ca>
cc: Ray Bellis <ray@bellis.me.uk>, dnsop@ietf.org
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Subject: Re: [DNSOP] Fundamental ANAME problems
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Joe Abley <jabley@hopcount.ca>; wrote:
>
> Specifically, I s the wildcard owner name a real problem in the grand
> scheme of things?

My understanding is that wildcards don't work for SRV because the
_prefixes are used to disambiguate which service you are asking for,
effectively to extend the RR TYPE number space. So if you wildcard a SRV
record then the target port has to support every possible protocol :-)

If you are using an _prefix without any meaning of its own but only to
move a record away from the apex (so that it can be delegated or CNAMEd)
and also using a specific RR type or an RDATA prefix, then wildcards do
not conflict.

Tony.
-- 
f.anthony.n.finch  <dot@dotat.at>;  http://dotat.at/
Viking, North Utsire, South Utsire, Northeast Forties: Southeasterly 6 to gale
8. Moderate or rough, occasionally very rough later. Occasional drizzle. Good,
occasionally poor.