How do I enable authentication for outgoing/sending mail with our server?
In the default config/install anyone can connect to our server and send mail to all users/domains on the server. The smtpd authentication only stops relaying to addresses outside the server.
I want to restrict sending mail with our server to ONLY authenticated users, and I think Postfix has a option called: smtp_sasl_auth_enable
But I canÂ´t find where and how to configure in Webmin/Virtualmin. If there is no option for this in Webmin/Virtualmin could someone point me in the right direction on how to set this up and enable it.