Forwarding mail

Hello. I am trying to forward each email that is sent or received by my MIAB to a address. I have managed to set the box up so that when an email is received it is forwarded onto the intended recipient and also to the backup. I have done this using an alias… so forwards to and also to I am slightly surprised that it woks as there does seem potential for an infinite loop?

However I cant work out how to do the same thing when any email is sent through my box, from one of my domains. I know this could be achieved using a bcc, but I really want to keep users out of this and implement this at the server end?

Any help always appreciated

It is something that can be accomplished by modifying the postfix config files I believe, but definitely something that I do not have experience with personally. A Google search should yield the answer

It would also be a unsupported modification, which means that when you upgrade the MiaB version, your modification would be lost and would have to be recreated.