INSTALL SPAMASSASSIN
Install the SpamAssassin package using yum by running:
## yum install spamassassin
SET-UP USER
create spamfilter group used for the user that will run the spamassassin service
## groupadd spamfilter
create new user spamfilter with a home directory of /usr/local/spamassassin and add it to the spamfilter group you just created
## useradd -g spamfilter -s /bin/false -d /usr/local/spamassassin spamfilter ## chown spamfilter: /usr/local/spamassassin
CONFIGURE SPAMASSASSIN
next, configure spamassassin by editing /etc/mail/spamassassin/local.cf and adding/setting the following
## vim /etc/mail/spamassassin/local.cf ## Required_hits: This determines the filter balance; the lower the score the more aggressive the filter. # A setting of 5.0 is generally effective for a small organisation or a single user. # Adjust the strictness score to your organizations needs - a large medical organisation might want to let email items # through that are trying to sell pharmaceuticals, so we might increase the level to a more modest 8.0. required_hits 5 ## Report_safe: This line determines whether to delete the item or to move the item to the inbox whilst appending # a spam notice to the subject line. The levels for this line are set to either a 1 or 0. A score of 1 will delete the spam item, # whereas a score of 0 will send the item to the inbox and rewrite the subject line. report_safe 0 rewrite_header Subject [**SPAM**] ## Required_score: This line sets the spam score for all email allowed through to your domain, with levels of certainty set from 0 to 5. # Zero would be classified as a legitimate email item, whereas 5 would be an definite SPAM item. If we set the score to 3 we would catch a # lot of unsolicited emails but quite a few false positives would still get through. For our example email server we will use the score of 5, # but you can of course set this value according to your preference. required_score 5.0
before we proceed with starting-up the spamassassin service, we need to make sure it runs with our newly created spamfilter user by editing /etc/sysconfig/spamassassin and setting-up the following:
## vim /etc/sysconfig/spamassassin
# Options to spamd
SAHOME="/usr/local/spamassassin"
SPID_DIR="/var/run/spamassassin"
SUSER="spamfilter"
SPAMDOPTIONS="-d -c -m5 --username ${SUSER} -H ${SAHOME} -s ${SAHOME}/spamfilter.log"
with all that in place, we are ready to start and enable the spamassassin service on system startup using:
## service spamassassin start ## chkconfig spamassassin on
CONFIGURE POSTFIX
next thing you need to do is to actually integrate spamassassin into postfix so it can scan and mark the emails that were detected as SPAM. To achieve this we need to edit postfix configuration file. Edit master.cf:
## vim /etc/postfix/master.cf
and add/edit the following lines:
smtp inet n - n - - smtpd -o content_filter=spamassassin
spamassassin unix - n n - - pipe user=spamfilter argv=/usr/bin/spamc -f -e /usr/sbin/sendmail -oi -f ${sender} ${recipient}
then, restart postfix for the changes to take effect
## service postfix restart