I would like to archive all incoming and outgoing mails by forwarding a copy of the mail to an additional SMTP server. I am aware that I can send BCC of all emails to a particular log account using always_bcc.

However I need to retain the original sender and receiver address in the SMTP handling, so that the archive server will process the mail with the corresponding control data. Using always_bcc the recipient header will get changed to the address where it will be copied.

To make myself more clear, if abc@xyz.com was the original recipient and log@archive.com was set in always_bcc, the SMTP on archive server will read the destination as log@archive.com and not abc@xyz.com My requirement is that the archive SMTP should also read the destination as abc@xyz.com itself.

I have been using Exim in the past for this, and I would simply add a router to accomplish the additional remote_smtp transport. What could be the equivalent of this in postfix?