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Re: [dmarc-ietf] DMARCbis WGLC Issue 136 - DMARC Records Can Be CNAMEs

Alessandro Vesely <vesely@tana.it> Fri, 15 March 2024 16:40 UTC

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Original-Subject: Re: [dmarc-ietf] DMARCbis WGLC Issue 136 - DMARC Records Can Be CNAMEs
Author: Alessandro Vesely <vesely@tana.it>
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Subject: Re: [dmarc-ietf] DMARCbis WGLC Issue 136 - DMARC Records Can Be CNAMEs
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On Fri 15/Mar/2024 02:34:15 +0100 Murray S. Kucherawy wrote:
> On Fri, Mar 15, 2024 at 9:11 AM John Levine <johnl@taugh.com> wrote:
> 
>> It appears that Todd Herr  <todd.herr@valimail.com> said:
>> >I agree that clarifying it can't hurt, obviously, ...
>>
>> I disagree, it does hurt.
>>
>> If we say you're allowed to use CNAMEs to point to DMARC records,
>> people are to say uh oh, is there something special here? What about
>> DKIM records? what about SPF records? how about SPF includes? or SPF
>> redirects?
>>
>> Really, there is nothing to say here, so let's not say it.
>>
> 
> +1, I don't understand what needs to be clarified here.  If I ask for a TXT
> record at a given name, I expect to get one back (or a non-success code).
> It really doesn't matter to DMARC whether that process traversed a CNAME
> record in the process.  (Or if it does matter, I've yet to see a reason
> why.)


+1, people who know DNS can derive the possibility to use CNAME on their own. 
Those who don't are better off not trying it.


Best
Ale
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