We're running a Postfix server configured to operate solely as an outgoing SMTP server. It does not have any local mailboxes setup.
We're having an issue when a message goes through the server and can't be delivered it attempts to bounce back to the sender. If it can't bounce back to the sender it then ends up being delivered to firstname.lastname@example.org. Since the root user is considered local the messages seem to pile up for a few days on the server until its eventually removed from the queue.
I'd like to change this so that it will send these undeliverable messages to myself: email@example.com. My mailbox is on a seperate system however.
How can I get the Postfix server to deliver these messages to another mailbox?