Routing all outgoing mail via the outgoing smarthost:

  1. Ensure the IP address is added as an Authorized Smarthost (without authentication)
  2. Ensure the Outgoing User has Enable Outgoing Connection Limits: ON
  3. Be sure that the correct limits are set matching your traffic volumes per Month, Week, Day, Hour and Minute
  4. Update your configuration using:

    echo ":SMARTHOST:587" > /var/qmail/control/smtproutes

  5. This will override any existing smtp routes. If you do not want this, you can replace the single > with >>.