Marek Podmaka via Postfix-users:
> On Sun, 14 Apr 2024 at 01:15, Wietse Venema via Postfix-users <
> postfix-users@postfix.org> wrote:
>
> > If there is a difference in deduplication, then you have introduced
> > a difference up-stream of the delivery agents. You need to find
> > that difference.
> >
>
...
> The differences between the servers are not large, the newer one is based
> on the older, with some settings changed to be more "how it should be
> currently done". On the old server (original config maybe 15 years old,
> with debian/postfix upgrades but minimal config changes), I prefer the
> "don't touch running system" approach, as modifying working parameters to
> be better (but with same functionality) could cause unpredicted issues.
> Both servers use the same underlying database structure.
This is an opportunity to use the "diff" command.
On the old system:
postconf -n > postconf-old
On the new system:
postconf -n > postconf-new
Compare the two with the diff command.
diff postconf-old postconf-new | less
If there are any differences besides domain names and the virtual
delivery agent versus the lmtp delivery agent, then make the
differences go away in the new Postfix.
At that point, the new Postfix will deduplicate recipients addresses
in the exact same way as the old one did.
If people forward messages with Dovecot sieve, then loops can happen.
You can configure the Postfix LMTP client to add a Delivered-to:
message header, and reject a message that it has already delivered
to the same recipient:
master.cf:
lmtp unix - - n - - lmtp flags=DX
main.cf:
lmtp_destination_recipient_limit = 1
See also:
https://www.postfix.org/lmtp.8.html
Sections "COMMAND ATTRIBUTE SYNTAX" and "SINGLE-RECIPIENT DELIVERY"
https://www.postfix.org/postconf.5.html#transport_destination_recipient_limit
Wietse
_______________________________________________
Postfix-users mailing list -- postfix-users@postfix.org
To unsubscribe send an email to postfix-users-le...@postfix.org
