Thanks, but I dont see how that answers the question. I have Discourse, and mail-receiver and I am familiar with a lot of Postfix and Dovecot, but I am aksing how I can get mail intended for Discourse routed by Postfix to mail reciever without interfereing with normal SMTP port 25 on the server. An yes I run Discourse reverse proxied with nginx.
Not being recommended is not a useful response, because then it means you have to have a dedicated server to only run Discourse and you cant run normal mail on it, if, as I need, you run mail-receiver for inbound email submissions. As to ‘config errors’ that is my responsibility and I am capable of dealing with that.
What I don’t know is the approach to take. Something with LMTP to mail-receiver on a different port?
When you say it worked for you, is this the scenario you have? If so, can you give more specific detail?