Jo?o Silva:
> Hi
>
> Recently I had some complains about the ammount of SPAM received.
>
> After some searches I found this page:
>
> https://www.linuxbabe.com/mail-server/configure-postscreen-in-postfix-to-block-spambots
>
> Since it looked like a good idea I decided to give it a try
>
> when I enabled postscreen in the server I did a test sending a email to
> see if things where working
>
> the logs showed that the smtp process was not resolving domains
>
> postfix/smtpd[14919]: NOQUEUE: reject: RCPT from unknown[209.85.128.45]:
> 450 4.1.8 <****@gmail.com>: Sender address rejected: Domain not found;
> from=<*****@gmail.com> to=<*******> proto=ESMTP
> helo=<mail-wm1-f45.google.com>
>
> When I deactivated postscreen everything went back to normal.
That's incorrect. Turning Postscreen on/off does not change how DNS
lookups work. In particular it does not change DNS lookups for the
Postfix smtpd process or for any other Postfix processes.
> Now the question:
>
> In the page that I mentioned earlier there is a note about CentOS 7 (the
> distribution that I am using) that tells to
First make postscreen work without turning on the postscreen chroot
feature and without messing with system libraries/configurations.
If you can't get that to work then don't use postscreen.
In other words, don't change system libraries/configurations AND
postcreen configuration at the same time.
Wietse
