[Mimedefang] Reject without PTR record

[Kris Deugau]

dimon at intellinetinc.com wrote:
> What do you think folks, is that a good idea to reject emails from
> relays with no PTR record?

Nope.

While it's not a problem on the systems I'm adminning now, a year ago
quite a large chunk of the internet could not seem to properly reach our
DNS to resolve reverse IP lookups on our IP blocks.  We had the records
in place, *some* systems could resolve our reverse lookups, but quite a
few didn't seem to be able to.

I would guess that while this isn't likely on larger providers, smaller
providers *do* get caught in the middle of someone else's DNS
problems/delays.

-kgd
-- 
"Sendmail administration is not black magic.  There are legitimate
technical reasons why it requires the sacrificing of a live chicken."
   - Unknown