Jose Borges Ferreira:
> On Wed, Dec 3, 2014 at 1:51 PM, Wietse Venema <wie...@porcupine.org> wrote:
> > Jose Borges Ferreira:
> >> This is the scenario.
> >> Box 1 : just receive email from "outside" - inbound flow.
> >> Box 2 : used to sent email to the "outside" - oubound flow.
> >
> > Inbound MTA: primary MX for your domain(s). If mail can't be
> > delivered, use Postfix's relayhost feature to deliver outbound mail
> > via the outbound MTA, if you can't use standard MX logic to deliver
> > directly to the sender's MX hosts.
>
> That's my initially idea, but was afraid that relayhost would "catch"
> more than intended.
It catches outbound mail. Postfix cannot generate other mail, as
long as all mail from inside has an inside envelope sender address.
And that is standard firewall hygiene.
Wietse
