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Questions tagged [postscreen]

Postscreen is a lightweight layer in front of postfix which performs simple tests on incoming connections to reduce the number of connections passed through to the actual SMTP-server thus reducing the server load.

Postscreen works on public-faced ports receiving connections from other mail servers. The purpose is to keep spambots away from Postfix SMTP server processes, while minimizing overhead for legitimate traffic.

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Postscreen sometimes stops the mail with 450 4.3.2 Service currently unavailable

I have a problem with postfix sometimes, inconsistently rejecting client mails: Sep 15 09:24:07 mail postfix/postscreen[16209]: NOQUEUE: reject: RCPT from [x.x.x.x]:15037: 450 4.3.2 Service currently unavailable; from=,…
drovak11
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Postfix Postscreen: how to use postscreen for smtp and smtps both

I'm trying to get postscreen work. I've followed the man page and it's already running correctly for smtp. But it I want to use it for smtps as well (adding the same line as smtp in master.cf but with smtps) i receive failure messages in syslog…
petermolnar
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Using both SpamAssassin and postscreen in Postfix

I'm trying to set up an MX server using Postfix, postscreen and SpamAssassin. According to the SpamAssassin documentation, I have to add -o content_filter to the smtp service in master.cf. This works with the default settings for Postfix, which is…
jornane
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How can I reject spam before reaching SMTP on Postfix

My server has started receiving thousands of attempts to use my mail server to send spam from dynamic.hinet.net. The attempts are always rejected, but it's non-stop. I'd like to block these attempts before they even reach the mail server is…
nutman
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