On Tue, May 18, 2021 at 09:26:40AM -0400, post...@ptld.com wrote:
> But for the single all in one server configuration, i tried:
>
> main.cf:
> virtual_transport=virtual
>
> master.cf:
> submission inet n - n - - smtpd
> -o virtual_transport=smtp:mxhost.example.com
>
> However the -o option under submission is ignored and the mail is still
> delivered to the virtual transport. Is there a way to split that
> behavior so transport in main.cf goes to virtual and transport under
> submission goes to smtp: ?
As I already noted in this thread, doing this on a single machines is
typically best accomplished via a MULTI-INSTANCE configuration, with
separate submission and relay instances.
Forwarding from submission to port 25 on the same machine generally runs
into loop detection issues. However, you may be able to avoid this by
setting the port 25 MTA as a proxy filter via:
http://www.postfix.org/postconf.5.html#smtpd_proxy_filter
submission inet n - n - - smtpd
-o smtpd_proxy_filter = [127.0.0.1]:25
This would also be more efficient, since there's no extra hop through
the queue. This will deliver all mail (whether for virtual users or
not) to port 25, from where it will then be routed appropriately.
Just make sure that 127.0.0.1 is in mynetworks, and not subjected
to excessive filtering, ...
--
Viktor.
