Postfix can be set up to replace smtpd entirely. Please read the
documentation at file:///usr/local/share/doc/postfix/html/index.html or
https://www.postfix.org/ carefully before you decide to do this!

To replace smtpd with Postfix you have to install a new mailer.conf
using the following command:

    /usr/local/sbin/postfix-enable

If you want to restore smtpd, this is done using the following command:

    /usr/local/sbin/postfix-disable
    
