I have a number of servers at a hosting space. What is the best way or is it possible to run a relay on one of the system to
send all emails to firstname.lastname@example.org to our email hosting service ? (we have our own DNS for myowndomain.com internally, but we host email service for the same domain on Microsoft 365. There's a public MX record)
send emails to email@example.com for our 3rd monitoring sevice?
Currently we tested running a dummy internal DNS to hardcode MX record for both myowndomain and monitoring.com. Postfix basically runs like a relay taking all emails and just forward out. I'm no expert of Postfix, wonder if this can be done correctly with postfix.