Re: [Acme] dns challenges and dynamic dns services (security considerations for domain holders)

"Patrick Burroughs" <celti@celti.name> Fri, 29 January 2016 14:34 UTC

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Date: Fri, 29 Jan 2016 07:34:30 -0700
From: "Patrick Burroughs" <celti@celti.name>
To: acme@ietf.org
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Subject: Re: [Acme] dns challenges and dynamic dns services (security considerations for domain holders)
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On Fri, 29 Jan 2016 14:47:57 +0100
Frederik Braun <fbraun@mozilla.com> wrote:

> [...] I would suggest that the dns challenge TXT record should
> maybe live
> on the domains TXT record itself?
> 
> e.g., dyndns.example IN TXT "_acme-challenge=value"

As I understand it, wouldn't this prevent you from setting challenges
for subdomains that are CNAMEs? A TXT record can't coexist with a CNAME
for the same subdomain.

Regards,
~Patrick