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:
