Alexandre Ellert:
>
> > Le 9 juil. 2015 ? 20:09, Viktor Dukhovni <postfix-us...@dukhovni.org> a
> > ?crit :
> >
> > On Thu, Jul 09, 2015 at 07:43:17PM +0200, Alexandre Ellert wrote:
> >
> >> I have an inbound MX in front of an Exchange Server and I?d like to
> >> DISCARD email when Exchange answer "554 5.1.0 Sender Denied" (and avoid
> >> backscatter)
Is that in reply to MAIL FROM, RCPT TO, DATA, or end-of-data?
If it is in reply to MAIL FROM, then one user would have veto rights
over what email other users can receive. That said, the reject can
be implemented in Postfix with check_sender_access.
If it is in reply to RCPT TO or DATA, then implementing the reject
in Postfix may require a policy daemon because Postfix currently
has no access table mechanism for (recipient, sender) pairs.
If it is in reply to end-of-data, then the Postfix 2.7 and later
SMTP client can rewrite the reply with smtp_reply_filter to "200
2.0.0 text...", causing Postfix to pretend that the mail was delivered
anyway, and dropping it from the queue.
Wietse
