Postfix DSN Support
Introduction
Postfix version 2.3 introduces support for Delivery Status
Notifications as described in
RFC 3464. This gives senders control
over successful and failed delivery notifications.
Specifically, DSN support gives an email sender the ability to
specify:
-
What notifications are sent: success, failure, delay, or
none. Normally, Postfix informs the sender only when mail delivery
is delayed or when delivery fails.
-
What content is returned in case of failure: only the
message headers, or the full message.
-
An envelope ID that is returned as part of delivery status
notifications. This identifies the message submission
transaction, and must not be confused with the message ID, which
identifies the message content.
The implementation of DSN support involves extra parameters to
the SMTP MAIL FROM and RCPT TO commands, as well as new Postfix
sendmail command line options that provide a sub-set of the functions
of the extra SMTP command parameters.
This document has information on the following topics: