dovecot with antispam plugin

Question

I am trying to enable antispam plugin for dovecot, but then dovecot stops working:

Jun  4 19:31:25 newmail dovecot: imap-login: Login: user=<tomasz_grobelny>, method=PLAIN, rip=127.0.0.1, lip=127.0.0.1, mpid=30714, secured, session=<eNurOLYXuQB/AAAB>
Jun  4 19:31:25 newmail dovecot: imap(tomasz_grobelny): Fatal: master: service(imap): child 30714 returned error 3

How do I track down why "child returned error 3"? Any chance for more verbose logs or being able to attach debugger? Obviously without the antispam plugin everything works just fine.

Answer 1

It may be too late to answer but I bumped into the same problem just now.

You posted your problem here so I assume that you might have ran Dovecot on Ubuntu. The problem is that pipe instead of mailtrain should be used for backend under Debian.

plugin {
  #setting_name = value
  antispam_backend = pipe
  antispam_mail_spam = --spam
  antispam_mail_notspam = --ham
  antispam_mail_sendmail = /usr/bin/sa-learn-pipe.sh
  antispam_spam = Junk
  antispam_trash = Trash
}

What's more, if you were following the tutorial from http://wiki2.dovecot.org/Plugins/Antispam , the pipe script there lacks several link breaks. So it should be:

#!/bin/bash

echo /usr/bin/sa-learn $* /tmp/sendmail-msg-$$.txt
echo "$$-start ($*)" >> /tmp/sa-learn-pipe.log

#echo $* > /tmp/sendmail-parms.txt
cat<&0 >> /tmp/sendmail-msg-$$.txt

/usr/bin/sa-learn $* /tmp/sendmail-msg-$$.txt && rm -f /tmp/sendmail-msg-$$.txt &

echo "$$-end" >> /tmp/sa-learn-pipe.log

exit 0