I have a raspberry pi running postfix. I Realised unless I open port 25 I absolutely cannot receive emails (I have 587 open and can send but not receive them). However I heard there are scaries online which someone could potentially send emails from your server without consent. I believe as well my ISP doesn’t block port 25. Is there anything I should do right now before opening port 25, or should everything be safe enough?
Hi, I recommend you read the book “Run Your Own Mail Server”. The fact that a book exists for this topic is all the proof you need to not do this decision. But if you absolutely must, this is the way.