Download location: Version used: &postfix-version; Package size: &postfix-size; Estimated Disk space required: &postfix-buildsize; The postfix package contains a Mail Transport Agent (MTA). This is useful for sending email to other users of your host machine. It can also be configured to be a central mail server for your domain, a mail relay agent or simply a mail delivery agent to your local Internet Service Provider (ISP). postfix depends on: