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

John Levine <johnl@taugh.com> Thu, 14 March 2024 23:07 UTC

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From: John Levine <johnl@taugh.com>
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Subject: Re: [dmarc-ietf] DMARCbis WGLC Issue 136 - DMARC Records Can Be CNAMEs
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It appears that Todd Herr  <todd.herr@valimail.com> said:
>The reasons given were:
>
>   1. https://www.rfc-editor.org/rfc/rfc5863#section-4.1

I am reasonably sure it was referring to DNS crudware that wouldn't
let you put an underscore in the name, or that limited TXT records to
a single 255 byte string, not CNAMEs.

>   2. https://datatracker.ietf.org/doc/html/rfc6376#section-7.5

I don't see that implying anything about CNAMEs.

>   3. Neither RFC 7489 nor DMARCbis contain the phrase "CNAME", so if it's
>   not explicitly mentioned...

I suggest we mark this "no change" and close it. There is a very short
list of RRTYPEs where you're not allowed to use CNAMES, and TXT isn't
on it.

R's,
John

PS: If anyone cares, the list contains NS and MX.  See RFC 2181, sec 10.3

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