Keith:
> I'm coming back into Postfix after not really needing to dig into it much
> the last few years and trying to
> catch up to some of the changes. Last version I really used heavily was 2.x
> something.
>
> Using version 3.2.2 under FreeBSD 11.
>
> I see a lot of these in the logs:
>
> Apr 30 01:51:42 mail1 postfix/smtpd[32690]: too many errors after AUTH from
> unknown[103.125.191.93]
> Apr 30 01:51:42 mail1 postfix/smtpd[32690]: disconnect from
> unknown[103.125.191.93] ehlo=1 auth=0/1 commands=1/2
I agree with the recommendations about port 25 AUTH and postscreen.
I don't enable AUTH on port 25, and I see very few AUTH attempts.
Additionally, postscreen can eliminate out a lot of spambots before
they even get to talk to a Postfix SMTP server process.
Wietse
