Postfix
Centralized set of programs to send/recieve mail, as well as put recieved mail through spam/virus filters.
Cyrus IMAP
SpamAssassin
Postfix uses SpamAssassin to filter e-mail
"If SpamAssassin is working, the message will be marked as spam. Note that SpamAssassin only marks messages as spam and that how it does this marking may be affected by your front-end. If you're not using the "spamc" or "spamassassin" program and are using a third-party front-end (especially amavisd), then it may not be completely obvious how spam messages are handled."[1]
AMaVis
amavisd:
- /etc/logrotate.d/amavisd
- /etc/cron.daily/amavisd
- /usr/sbin/amavisd
- and more. . .
amavis.org on Postfix: "FIXME: For now please read the provided file README.postfix"
/usr/share/doc/amavisd-new-2.4.3/README.postfix on einstein goes into great detail on how to set amavis up with postfix.
Turns out we may be running amavisd-new, which likes to pretend it's amavisd.
GNU Mailman
Manages mailing lists.
Web interface on einstein
More info