[dns-operations] cloudflare-dns.com doesn't have reverse DNS

[Joe Abley]

Op 19 sep 2023 om 18:52 heeft Fred Morris <m3047 at m3047.net> het volgende geschreven:

> But notice that their infrastructure servers do have reverse DNS.

I will freely admit that I am old enough to like reverse DNS and that it makes my eyes itch a little bit when it's not there. 

> I don't know that I really have an ask here, other than an observation that it's nice when DNS works; and when it doesn't it's not that difficult to synthesize PTR records from observed traffic. (Further editorializing deleted.)

I have a tangential question, studiously avoiding the question of what Cloudflare does or doesn't or should or shouldn't do. (I work for Cloudflare.)

For a long time now it has seemed that reverse DNS is important in a real and practical sense if you want to send mail and have someone else accept it. 

Traceroutes are more informative when they have names to go along with the numbers, but there are big parts of the world who never got that memo, ever, so it's a bit of a stretch to say that's a hard requirement. 

IANA will send back root zone change requests with red ink on them if they involve adding a nameserver to a delegation that doesn't have reasonable reverse DNS, I think. At least, that used to be true. I don't think there are consequences if the reverse DNS disappears later though. 

Apart from mail and some degree of debugging courtesy, what operational reasons exist to put effort into reverse DNS in 2023? Are there any? Or is the whole reverse tree just a weird anachronism?


Joe