Milter-greylist

"Thomas Cameron thomas.cameron@..." writes:
>
> I had a mail conversation with someone today. They use some Amazon
> hosted mail service. The first email came from [sender1] and was relayed
> through ec2-54-153-11-11.us-west-1.compute.amazonaws.com. The second
> mail came from [sender1] but from
> ec2-54-153-22-22.us-west-1.compute.amazonaws.com, and so on. Every new
> e-mail wound up coming through a different relay on Amazon.
>
> What winds up happening is, EVERY new e-mail is delayed, often times
> several hours because they don't retry in a timely fashion.

[This list has bad behavior with Reply-To and rewriting the sender....]

A few ideas:

* There's a notion of whitelisting address ranges that are inhabited by
  this kind of distributed retrying.

* In an age where greylisting is normal, it's buggy of a sender not to
  retry from the same address.  Good luck with that approach :-)

* Perhaps milter-greylist could by default or could be configured to
  consider hosts in the same /24 (not enough for your case) or /16 to be
  the same.

What I do is just add whitelist entries when I have trouble.