v3.1 configuration example

Postfix submission service

Review and adapt this example to your topology, product version and security requirements.

submission inet n - n - - smtpd
  -o syslog_name=postfix/submission
  -o smtpd_tls_security_level=encrypt
  -o smtpd_sasl_auth_enable=yes
  -o smtpd_relay_restrictions=permit_sasl_authenticated,reject

Important: replace example addresses, credentials, hostnames and paths. Validate syntax before deployment.