On Mon, 2009-08-03 at 16:44 +0900, Christian Balzer wrote: > So how do people keep a backup (meaning only mails that actually got a > final delivery, splitting things off earlier is trivial of course) of > incoming mails on a remote server then?
I guess this depends upon what you define as "final delivery", doesn't it? Do you mean: A. Only take a backup copy of a message once it has successfully completed delivery into a user's mailbox, or B. Take a backup copy as part of the operation of delivering into the user's mailbox - there's a minor, but significant, difference between those two statements. At work, on our Exim+CourierIMAP based "postbox" servers - that is, the ones which the users access via an IMAP client to read their mail - we have a shadow router/transport pair which copy the mail to a short-lived "Incoming Mail Backup" maildir: Router is: localuser_backup: driver = accept check_local_user address_data = <condition removed> transport = local_delivery_backup unseen Transport is: local_delivery_backup: driver = appendfile directory = $home/Incoming-Mail-Backup user = $address_data delivery_date_add return_path_add maildir_format That pair run immediately before the local delivery router puts the message in the user's mailbox. It's not a great stretch of logic to change the transport to be a remote one. *However* - this happens immediately before the message is delivered into the user's mailbox, so could quite conceivably store the backup copy yet have a problem with the actual delivery, causing the message to be lost. Yes, this is the entire point of the backup operation, in case you were wondering! I guess you could invert the sequence, and make the *actual* delivery "unseen" and then do the remote one but that would make error handling more difficult. What would your definition of "final delivery" be? Graeme -- ## List details at http://lists.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://wiki.exim.org/
