Am 27.09.2017 um 09:35 schrieb Thomas Bauer:
On the postfix server in master.cf:
submission inet n - - - - smtpd
...
-o smtpd_sasl_path=inet:192.0.0.1:10001
...
You might use
-o smtpd_tls_security_level=encrypt
as well, to ensure postfix make use of tls.