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

[Fred Morris]

On Fri, 22 Sep 2023, Joe Abley wrote:
> 
>> Op 22 sep 2023 om 16:26 heeft Grant Taylor <gtaylor at tnetconsulting.net> het volgende geschreven:
>> 
>> I have long viewed operational, or better accurate, reverse DNS as an 
>> indication that a network cares enough to set up lesser valued 
>> services.
>
> Me too, actually. I don't personally think it's the only such 
> indication, or a particularly strong one, even, but I agree with you.
>
> So, mail sending, traceroute and marketing to niche technical audiences? 
> :-)

I think what's happening with cloudflare-dns reflects my working 
hypothesis, which is that infrastructury stuff has a higher likelihood of 
having reverse DNS attended to and cloudy, direct to consumer stuff has a 
lower likelihood.

In some cases CNAME chains obviously make the commonly understood meaning 
of reverse DNS "operational but not accurate", but not the intent in my 
opinion. In other cases (looking at you, Fastly) you just get back 
NXDOMAIN.

In the field, I seldom see a single address serving content across 
multiple entities of control (businesses) at a given point in time, what I 
see is more along the lines of e.g. cdn.technologynetworks.com and 
www.technologynetworks.com both resolve to the same address, and one is 
probably queried more than the other.

The question in my mind is how often the same entity controls the forward 
domains and the relevant reverse domains, because there is little to no 
technical impediment in that case for generating and publishing a 
notional-as-to-intent reverse DNS entry from their own forward emissions. 
I give away software on GitHub to do that for consumer/client networks 
today (pay particular attention to the heuristic for choosing which option 
of many to generate the record for, so there is a single record best 
reflecting intent).

--

Fred Morris