Aliases

Please read the Postfix documentation on virtual aliases first.

You can use setup.sh instead of creating and editing files manually. Aliases are managed in /tmp/docker-mailserver/postfix-virtual.cf. An alias is a full email address that will either be:

delivered to an existing account registered in /tmp/docker-mailserver/postfix-accounts.cf
redirected to one or more other email addresses

Alias and target are space separated. An example on a server with domain.tld as its domain:

# Alias delivered to an existing account
alias1@domain.tld user1@domain.tld

# Alias forwarded to an external email address
alias2@domain.tld external@gmail.com

Configuring RegExp Aliases

Additional regexp aliases can be configured by placing them into config/postfix-regexp.cf. The regexp aliases get evaluated after the virtual aliases (/tmp/docker-mailserver/postfix-virtual.cf). For example, the following config/postfix-regexp.cf causes all email to "test" users to be delivered to qa@example.com:

/^test[0-9][0-9]*@example.com/ qa@example.com

Address Tags (Extension Delimiters) an Alternative to Aliases

Postfix supports so-called address tags, in the form of plus (+) tags - i.e. address+tag@example.com will end up at address@example.com. This is configured by default and the (configurable !) separator is set to +. For more info, see How to use Address Tagging (user+tag@example.com) with Postfix and the official documentation.

Note

If you do decide to change the configurable separator, you must add the same line to both config/postfix-main.cf and config/dovecot.cf, because Dovecot is acting as the delivery agent. For example, to switch to -, add:

recipient_delimiter = -