> On Apr 14, 2018, at 12:23 AM, Christos Chatzaras <ch...@cretaforce.gr> wrote:
>
> I think the only way to fix this is to have 2 postfix instances, right? One
> for incoming and one for outgoing.
If you want to round-trip mail through an external SMTP server,
and then bring it back to the same host, then yes, there typically
need to be two queues (Postfix instances), one that sends all mail
out, and another that accepts and delivers.
One can play games with rewriting, so that mail originally rewrites
to a domain that goes off-box, possibly rewrites in the outbound
smtp delivery agent smtp_generic_maps, and then returns into an
smtpd(8)/cleanup(8) pair that does no or different rewriting.
That could make it possible to use a single queue, because the
destination domain would be different for returned mail than
for originally incoming mail.
--
Viktor.
