alt Hacker NewsWhile nothing good can be said about the design of DNSSEC here, it seems to me that the new np feature’s semantics are also misguided. I get it: if I own company.com and I’m not using foo.company.com, then maybe I should set np=reject on company.com’s DMARC rule so that no one can spoof email from it.
But it seems odd that www.company.com should be considered present for this purpose even if it has no MX records. And if I want to send from noreply.company.com, then setting some unrelated DNS record type there to prevent it from being not “not present” seems like a giant kludge.
And lots of domains have subdomains that are intended for some non-email purpose (api.company.com or whatever), and those shouldn’t be allowed without further policy. Nor should (technically invalid for SMTP but maybe allowed anyway) delights like _dmarc.company.com itself.
Why didn’t the DMARC spec say that a domain is “not present” if it lacks MX records?
> Why didn’t the DMARC spec say that a domain is “not present” if it lacks MX records?
MX implies a domain can receive email, you don't need it to send email. A setup where company.example sends email from companymailings.example but sets a reply-to for [email protected] is perfectly valid (even if it's stupid and confusing). Plus there's that weird legacy behaviour of mail servers delivering to port 25 to the IP in the A record if MX records are missing.