Tessa Plum: > Hi Wietse, > > As an incoming MTA, after Postfix receive messages, which part takes the > duty of saving messages to disk?
The cleanup(8) daemon writes incoming mail to a queue file. There are about a dozen other daemons that read from a queue file. > Is this possible that messages were stored into disk by encrypted? One solution is to use full-disk encyption i.e. there are no keys stored as plaintexxt on the disk, the disk is unreadable when the server is shut down, and Postfix does not manage encryption keys. Otherwise, Postfix would need to manage encryption keys to store messages and decryption keys to deliver messages. The big question is The big question is where would Postfix get the keys from? They should not be stored as plaintext on the disk. If you want encryption only, then you will need an external milter or external content filter that replaces plaintext content with encrypted content. See http://www.postfix.org/CONTENT_FILTER_READ+ME.html for an overview of the options. Wietse
