Spamassassin

Warning:

This page is a work in progress and is not completed. Important informations might be missing or wrong.

Install

# apt install spamassassin

edit file /etc/spamassassin/local.cf

bayes_path /var/lib/spamassassin/bayes_db/bayes
bayes_file_mode 0770

# mkdir /var/lib/spamassassin/bayes_db

Training

To reach a good efficiency, SpamAssassin Bayesian filter need to be trained with both spam and ham messages. You can use your actual mailbox for that but note the following points:

• Be sure that the folders you use for training contain only spam or ham. If a folder contain a mix of them, SpamAssassin will learn wrong info and produce bad quality results
• To be effective you need between 1000 and 5000 messages each of both spam and ham.
• You need to have more ham than spam to train. Otherwise, SpamAssassin might become biased toward spam.

# sa-learn --spam --showdots --dir /var/maildir/<username>/Maildir/.Spam/cur/
# sa-learn --ham --showdots --dir /var/maildir/<username>/Maildir/cur/

Integrate with exim

# apt install sa-exim

Integrate with dovecot

# apt install dovecot-antispam

In file /etc/dovecot/conf.d/20-imap.conf, modify the option mail_plugins and add antispam to the list

protocol imap {
  # Space separated list of plugins to load (default is global mail_plugins).
  mail_plugins = $mail_plugins antispam
}