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Preventing daily mail status reports from being blocked

The following is quoted from Jim Seymour's Pflogsumm FAQ at http://jimsun.linxnet.com/downloads/pflogsumm-faq.txt. Pflogsumm is a program that analyzes Postfix logs, including the logging from rejected mail. If these logs contain text that was rejected by Postfix body_checks patterns, then the logging is also likely to be rejected by those same body_checks patterns. This problem does not exist with header_checks patterns, because those are not applied to the text that is part of the mail status report.

You configure Postfix to do body checks, Postfix does its thing, Pflogsumm reports it and Postfix catches the same string in the Pflogsumm report. There are several solutions to this.

Wolfgang Zeikat contributed this:

#!/usr/bin/perl
use MIME::Lite;

### Create a new message:
$msg = MIME::Lite->new(
    From     => 'your@send.er',
    To       => 'your@recipie.nt',
    # Cc     => 'some@other.com, some@more.com',
    Subject  => 'pflogsumm',
    Date     => `date`,
    Type     => 'text/plain',
    Encoding => 'base64',
    Path     => '/tmp/pflogg',
);

$msg->send;

Where "/tmp/pflogg" is the output of Pflogsumm. This puts Pflogsumm's output in a base64 MIME attachment.

Note by Wietse: if you run this on a machine that is accessible by untrusted users, it is safer to store the Pflogsumm report in a directory that is not world writable.

In a follow-up to a thread in the postfix-users mailing list, Ralf Hildebrandt noted:

"mpack does the same thing."

And it does. Which tool one should use is a matter of preference.

Other solutions involve additional body_checks rules that make exceptions for daily mail status reports, but this is not recommended. Such rules slow down all mail and complicate Postfix maintenance.