PostFix per Username Authentication

To use an authenticated user:

  1. Create a password maps file, for example /etc/postfix/relay_passwd:

    2. smtp.smarthostname.demo-domain.invalid USERNAME:PASSWORD"

  2. Ensure the file has the correct permissions and to create the hash from the maps file by executing the following commands:
    • chown root:root /etc/postfix/relay_passwd
    • chmod 600 /etc/postfix/relay_passwd
    • postmap /etc/postfix/relay_passwd
  3. Add the following line to /etc/postfix/main.cf

    4. relayhost = SMARTHOST:587

  4. Finally add the following to /etc/postfix/main.cf below the relayhost = line:

    5. smtp_sasl_auth_enable = yes
    smtp_sasl_password_maps = hash:/etc/postfix/relay_passwd
    smtp_sasl_security_options =

  5. Restart Postfix for the changes to take effect using /etc/init.d/postfix restart