Milter-greylist

Matt Kettler wrote:

> 
> 
> My sendmail *does* reject nonexistent senders, and always has. re-read my
> message. The rejection happens *AFTER* the greylist runs.

I realized that's not all that clear.

Let me clarify.

My mailserver will never accept mail to a nonexistent user. I'm not describing
post-delivery bounces, it will will never allow a SMTP data phase to start.

However, when a remote server connects and tries to deliver mail,
milter-greylist declares the message greylisted. This happens _before_ sendmail
checks to see if the user exists.

The second time they connect (if they do) milter-greylist will allow the message
past, and then sendmail will 550 the message with an unknown user error.

All of this happens before the data phase in both cases.

If milter-greylist was not installed they'd have gotten a 550 the first time,
but it appears that on my server the order of operations is such that
milter-greylist runs before sendmail does any checks to see if the recipient exists.