Ask Slashdot: Is Reverse DNS a Worthy Standard For Fighting Spam?

drmartin66 makes it to the front page with this question: "Last weekend I installed a new spam filter server for a client, and enabled connection rejection if the sending server did not have a Reverse DNS record. Since then, I have had a number of emails rejected from regulator bodies that do not have a Reverse DNS record, and are refusing to have one created for their email server. What is your opinion of Reverse DNS records? Are they (or should they be) a standard, and required? Or are they useless for spam fighting?"

Comments

Re:rDNS

[SmurfButcher Bob]

I don't think the actual internet works the way you think it does. However, I have no doubt that your view is perfect for the very simplified myopic universe you live in.

Things like OpenDNS.com should make you shut up, hopefully. If it doesn't, then perhaps the DNS hosting provided by NetSol and Dotster and that ilk, will. And please do not comment on the impact of screwed BGP if you don't comprehend how it affects peering. If you actually insist that a DNS query to god-knows-what server is going to take the exact same route to god-knows-some-MTA on another ASN, you're a moron. If you actually insist that the PTR records are hosted on the same DNS server that MTA uses for resolution, you're an even a bigger moron.

That, or you have not the slightest clue as to what you are talking about. From a reliability standpoint, PTR checks are horrible risk with low value.