Install SpamAssassin on a debian sever for the postfix mail server 05.12.19

Step 1: Install SpamAssassin and its client

$ apt-get install spamassassin spamc

Step 2: Add a user for the spamd daemon

$ adduser spamd --disabled-login

Step 3: Edit the configuration settings at /etc/default/spamassassin

I'll only list the values I'm changing.

# Change to one to enable the spamd daemon
ENABLED=1

# Set the username, home directory and log file
SPAMD_HOME="/home/spamd/"
OPTIONS="--create-prefs --max-children 5 --username spamd --helper-home-dir ${SPAMD_HOME} -s ${SPAMD_HOME}spamd.log"

# Set a location for the Process ID file
PIDFILE="${SPAMD_HOME}spamd.pid"

# Set the sa-update process to update the anti-spam rules automatically on a nightly basis
CRON=1

Step 4. Edit /etc/spamassassin/local.cf to set up some anti-spam rules

I use the following settings:

rewrite_header Subject ***** SPAM _SCORE_ *****
report_safe             0
required_score          5.0
use_bayes               1
use_bayes_rules         1
bayes_auto_learn        1
skip_rbl_checks         0
use_razor2              0
use_dcc                 0
use_pyzor               0

This will cause each email that scores 5.0 or greater on its spam checks to marked with ***** SPAM ***** and the score in its subject line. Most email clients already recognize the headers or text that SpamAssassin adds to incoming emails, but if you have a client that doesn't, you can set up a filtering rule to send any message with ***** SPAM ***** in its subject line directly to your junk folder.

The "bayes" rules allow the Bayesian filter to try to identify spam. And if report_safe is set to 0, incoming spam will be identified by "X-Spam-" headers added to the message while no changes are made to the message body.
Step 5: Tell Postfix to pass incoming messages to the anti-spam system for checking

Edit /etc/postfix/master.cf and add a content filter to your SMTP server:

smtp      inet  n       -       -       -       -       smtpd
        -o content_filter=spamassassin

Still in /etc/postfix/master.cf, add this to the end of the file:

spamassassin unix -     n       n       -       -       pipe
        user=spamd argv=/usr/bin/spamc -f -e  
        /usr/sbin/sendmail -oi -f ${sender} ${recipient}

This tells the client to pass its completed checks to the default MTA (mail transfer agent, /usr/sbin/sendmail, i.e., the Postfix-Sendmail compatibility interface) for handoff to the MDA (mail delivery agent, Dovecot) for delivery.
Step 6: Start/restart everything and test

$ service spamassassin start
$ service postfix restart

https://www.geoffstratton.com/spamassassin-ubuntu

Anonymous

Install SpamAssassin on a debian sever for the postfix mail server 05.12.19

Information Epoch 1714079528