Postfix Cheat Sheet

Configuring Postfix to use Dovecot’s SASL implementation

The Ubuntu guide, at https://help.ubuntu.com/community/PostfixDovecotSASL, makes it easy.

Virtual alias domains

Assuming DNS is properly set up:

First, list domains in the virtual_alias_domains setting in main.cf. e.g.:

virtual_alias_domains = example.org example.com
virtual_alias_maps = hash:/etc/postfix/virtual

Next, edit the virtual map (/etc/postfix/virtual, in this case) to have the virtual domain address. e.g.:

# Example.org
foo@example.org    foo@clapper.org

# Example.com
foo@example.com    devnull@clapper.org

Then, run postmap to update the map:

$ sudo postmap /etc/postfix/virtual

DomainKeys

Using dkim-filter:

https://help.ubuntu.com/community/Postfix/DKIM