Amavisd-newRevisionas of Sunday, 20 December 2015 at 19:56 UTC

For CentOS 6.4, with SpamAssassin 3.3, Amavisd-new 2.8, and ClamAV 0.97

Amavisd-new takes a message from
Postfix, gives it to content checkers like
ClamAV and
SpamAssassin, and hands the message
back to Postfix, which then decides what to do with it (i.e., reject,
keep it in hold, and so on)¹.

I learned a lot about this from this excellent
guide.

Installation

   # Install
   yum install amavisd-new clamav spamassassin

   # Start
   chkconfig amavisd on; service amavisd start
   chkconfig clamd on; service clamd start
   chkconfig spamassassin on; service spamassassin start

   # Update
   freshclam
   sa-update

You’ll have to update only once; both ClamAV and SpamAssassin come with
their own cron jobs. Handy.

Configuration

Miscellanous

• I was partial to MailScanner,
  another Perl-based interface which looks like a breeze to install.
  However, the Postfix docs say
  it uses “unsupported methods to manipulate Postfix queue files
  directly.” Okay.
• SpamAssassin can be a bit daunting to configure. I found this
  online
  configurator helpful.

Footnotes