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Postfix: log message from, to and subject

Published: 28-03-2009 | Author: Remy van Elst | Text only version of this article

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This is a little trick for Postfix, it lets you log the subject, from and to of all the emails postfix sends (or which pass through it if you run it as a relay). It comes in handy when you need to debug an email issue and need to confirm your mailserver has sent the message.

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First create the file /etc/postfix/header_checks and insert this into it:

/^subject:/      WARN
/^to:/           WARN
/^from:/         WARN
/^Subject:/      WARN
/^To:/           WARN
/^From:/         WARN

Now, in your postfix /etc/postfix/ add the following to the end of the file:

header_checks = regexp:/etc/postfix/header_checks

And restart postfix:

service postfix restart

You will hopefully now get log items like below, and if not you have a problem with your mailserver:

Dec  4 08:23:05 localhost postfix/cleanup[2278]: 90CA714: warning: header
Subject: This is a testmail which gets logged from localhost[];
from=<root@localhost> to=<root@localhost> proto=ESMTP helo=<localhost>
Tags: logging , mail , mta , postfix , tutorials