How does amavis talk to spamassassin?

Question

I'm going through all the amavisd-new config files, and I can't find anything that tells amavis to talk to spamassassin/spamd to get a spam score. The reason I ask is because I'd like to swap out spamassassin for dspam, and am wondering how amavis is wired up.

Answer 1

Amavis/Amavisd-new works as a filtering service. The general flow is Internet -> Postfix (or other) -> Amavisd-new -> Antispam -> Amavis -> A/V -> Postfix -> mailbox.

In the specific case of spamassassin the default config of amavisd is to invoke it directly via the perl module Mail::SpamAssassin. If memory serves right the examples (at least on debian) had quite a good commented configuration.

Generally speaking you need to tell amavis to send the mail on a socket (net/local/etc) and the thing on the other end of this socket should return the proper status.

More info can be found: http://wiki.apache.org/spamassassin/IntegratedInPostfixWithAmavis

A bit dated howto for dspam: http://help.ubuntu.ru/wiki/amavis_clamav_dspam_ubuntu_10_04 (in Russian but translate should deal with it)

Answer 2

Never mind, I figured it out. The file /usr/share/doc/amavisd-new/examples/amavisd.conf-default.gz contains the following line:

# @spam_scanners = ( ['SpamAssassin', 'Amavis::SpamControl::SpamAssassin'] );

So this is a default value that I wasn't seeing in my /etc/amavis/conf.d folder.