Postfix VERP Howto

Postfix VERP support

Postfix versions 1.1 and later support variable envelope return path addresses on request. When VERP style delivery is requested, each recipient of a message receives a customized copy of the message, with his/her own recipient address encoded in the envelope sender address.

For example, when VERP style delivery is requested, Postfix delivers mail from "owner-listname@origin" for a recipient "user@domain", with a sender address that encodes the recipient as follows:

owner-listname+user=domain@origin

Thus, undeliverable mail can reveal the undeliverable recipient address without requiring the list owner to parse bounce messages.

The VERP concept was popularized by the qmail MTA and by the ezmlm mailing list manager. See https://cr.yp.to/proto/verp.txt for the ideas behind this concept.

Topics covered in this document:

• Postfix VERP configuration parameters
• Using VERP with majordomo etc. mailing lists
• VERP support in the Postfix SMTP server
• VERP support in the Postfix sendmail command
• VERP support in the Postfix QMQP server