ByteME

apt-get install postfix

# See /usr/share/postfix/main.cf.dist for a commented, more complete version smtpd_banner = $myhostname ESMTP $mail_name (Debian/GNU) biff = no # appending .domain is the MUA's job. append_dot_mydomain = no # Uncomment the next line to generate "delayed mail" warnings #delay_warning_time = 4h myhostname = mail.mydomain.com alias_maps = hash:/etc/aliases alias_database = hash:/etc/aliases myorigin = /etc/mailname relay_domains = mydomain.com, localhost.localdomain, localhost relayhost = 192.168.0.20 mynetworks = 127.0.0.0/8 mailbox_command = mailbox_size_limit = 0 recipient_delimiter = + content_filter = smtp-amavis:[127.0.0.1]:10024 For the relay setup it i important to get the relay_domains correct or the server will refuse to accept incomming email. It is also important that mydestination is not set or the server will collect mail itself and not forward it on. The content_filter entry is part of the amavis-new setup next. This should at this stage (with out the content_filter line) funtion as a relay server and can be tested in this state.

amavisd-new

To install :-

apt-get install amavisd-new

The configuration of amavisd is more complex and requires adjustments to postfix as well. Firstly it is necessary to add in the content_filter line to /etc/postfix/main.cf. Then the /etc/postfix/master.cf should be configured to call amavisd.
/etc/postfix/master.cf should have these lines added :-

smtp-amavis unix -      -       -       -       2       smtp 
    -o smtp_data_done_timeout=1200 
    -o disable_dns_looks=yes

127.0.0.1:10025 inet n  -       -       -       -       smtpd
    -o content_filter=
    -o local_recipient_maps=
    -o relay_recipient_maps=
    -o smtpd_restrictions_classes=
    -o smtpd_client_restrictions=
    -o smtpd_helo_restrictions=
    -o smtpd_sender_restrictions=
    -o smtpd_recipient_restrictions=permit_mynetworks,reject
    -o mynetwork=127.0.0.0/8
    -o strict_rfc821_envelopes=yes

ClamAV

ClamAV is my prefered (open source) antivirus option and i installed the clamd version (daemon)

apt-get install clamav-daemon

In the questions i selected to use the daemon mode of freshclam as well to keep the virus definitions upto date. The amavisd config file seemed to have clamav options already enabled so it was (almost) ready to use out of the box for me:-) this is what i found in /etc/amavis/amavisd.conf:- (i did have to adjust the path for clamd.ctl, it is shown below)

### http://www.clamav.net/
['Clam Antivirus-clamd',
  \&ask_daemon, ["CONTSCAN \n", "/var/run/amavis/clamd.ctl"],
  qr/\bOK$/, qr/\bFOUND$/,
  qr/^.*?: (?!Infected Archive)(.*) FOUND$/ ],
# NOTE: run clamd under the same user as amavisd;  match the socket
# name (LocalSocket) in clamav.conf to the socket name in this entry
# When running chrooted one may prefer: ["CONTSCAN \n","$MYHOME/clamd"],

There was one issue with access to ClamAV from amavis, to solve this I made clamav run as user amavis and had the contrl file inside alavis' home directory by changing the following two options in /etc/clamav/clamav.conf

LocalSocket /var/run/amavis/clamd.ctl
User amavis

Spamassassin

Spamassassin support is also native to amavisd-new but you still need the spamassassin packages

apt-get spamassassin

should do it. can't remember exatly what i did left notes at work!, tomorrow maybe :-)