On Sunday, December 5, 2021 2:04:20 PM EST John Levine wrote: > It appears that Scott Kitterman <[email protected]> said: > >Should we modify the definition of non-existent domains so that a domain > >that only has an RFC 7505 null mx record is still considered non-existent? > How about if it has a null MX and a DMARC record or DKIM keys? Remember > that those records are at different names than the MX. > > This sounds like local policy again. Personally, I am not crazy about > getting mail that I can't reply to, but my mailbox is full of mail from > my bank and stores from which I have ordered telling me that I can't reply > to their messages.
There's two ways we could go at this question: 1. A domain that, except for the null mx, would fit the criteria for non- existent. This would be kind of weird, since mull mx only makes sense if you have an A/AAAA, but I wouldn't think existence of a null mx alone would be enough to make the domain 'exist'. 2. A domain which has an A/AAAA and null mx. Since it claims to be a no mail domain, we could treat it as not existing for DMARC purposes. Since RFC 7505 specifies null mx is for domains that don't accept mail, but is silent on sending mail, these should probably exist for DMARC purposes. I think that your point is about #2 and I agree. #1 is definitely a corner case, but if the only thing there is a null mx, I'd be quite comfortable saying it doesn't exist. Scott K _______________________________________________ dmarc mailing list [email protected] https://www.ietf.org/mailman/listinfo/dmarc
