E-mail

This is the set of programs that service NPG e-mail.

The order of operations for starting mail by hand is as follows: Dovecot, Spamassassin, Postfix, Mailman.

And to safely stop the mail system, stop the services in this order: Mailman, Postfix, Spamassassin, Dovecot.

The reason for this order is we stop recieving mail from other servers once postfix is down, stop processing incoming/outgoing mail with spamassassin because there's no more incoming/outgoing mail, and then we stop users from being able to get their mail and change things with dovecot. This allows us to take the mail system down and not bounce or lose any, since the servers trying to send us mail simply wait until we're receiving again.

Postfix

Centralized set of programs to send/recieve mail, as well as put recieved mail through spam/virus filters. The RPM is pretty good in that it automatically puts entries for some of the below programs in the appropriate configuration files. Sometimes it's necessary to un-comment them, though.

Dovecot

We run dovecot as our mail server. We're using a pretty much default setup, for ease of administration. The dovecot website has all necessary documention, and most of the system is fairly self-explanatory.

SpamAssassin

Postfix uses SpamAssassin to filter e-mail. Needs an entry in /etc/postfix/master.cf and Procmail configuration

• Start Using SpamAssassin links
• Already Using SA tips

Presently, we only mark spam with some header flags, and by prepending "[SPAM] " to the subject of spammy messages. Due to issues with forwarding spammy messages, we are quietly purging all spam mail. Because we have fairly conservative settings, this should not cause any problems.

GNU Mailman

Manages mailing lists.
Web interface on einstein
More info