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Configuring postfix to fight spam, 2012 edition





EDIT: This question was poorly asked,
later I found another question which answers what i wanted to know: href="https://serverfault.com/questions/17221/spam-prevention-tips-for-postfix">Spam
prevention tips for Postfix



I'm
running a small (20 users, 30 mailman-lists) server with postfix. I think it's
configured fine, more or less. I spent 2 days reading up on all kinds of material on
postfix configuration, but I couldn't find any list of measures that are actually safe
to enable/disable. For about every configuration option i found there were some people
pro and some against it.



This is my postfix
configuration, can you give me simple measures on what to
improve?



alias_database =
            hash:/etc/aliases, hash:/var/lib/mailman/data/aliases
alias_maps =
            hash:/etc/aliases,
            hash:/var/lib/mailman/data/aliases

append_dot_mydomain =
            no
biff = no
config_directory =
            /etc/postfix
disable_vrfy_command = yes
home_mailbox =
            Mail/
inet_interfaces = all
mailbox_command = /usr/bin/spamc -e
            /usr/lib/dovecot/deliver
mailbox_size_limit = 0
mydestination =
            localhost, .at, .at
myhostname =
            .at

mynetworks = 127.0.0.0/8
            [::ffff:127.0.0.0]/104 [::1]/128
myorigin =
            /etc/mailname
readme_directory = no
recipient_delimiter =
            +
smtpd_banner = $myhostname ESMTP
smtpd_delay_reject =
            yes
smtpd_helo_required = yes
smtpd_recipient_restrictions =
            permit_mynetworks, permit_sasl_authenticated,
            reject_unauth_destination
smtpd_sasl_auth_enable =
            yes
smtpd_sasl_local_domain = $myhostname

smtpd_sasl_path
            = private/auth
smtpd_sasl_type = dovecot
smtpd_tls_CAfile =
            /etc/ssl-certs/startssl.chained.crt.pem
smtpd_tls_cert_file =
            /etc/ssl-certs/startssl.our.crt.pem
smtpd_tls_key_file =
            /etc/ssl-certs/private/startssl.key.pem
smtpd_tls_received_header =
            yes
smtpd_use_tls = yes
soft_bounce = no
tls_random_source
            =
            dev:/dev/urandom



Also
recently I read something about BATV, and from reading my /var/log/mail.info i think i
have quite a few messages being invalid bounces.



Answer




check this tutorial. it's getting quite regularly updated - i used it ~5
yrs ago, i used it ~half year ago. it tells about the whole ecosystem [amavis,
spamassasin, dcc, pyzor, razor and more], not just postfix.



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