Matt Corallo:
>
>
> On 8/11/21 13:54, Viktor Dukhovni wrote:
> >> On 11 Aug 2021, at 11:00 am, Matt Corallo <ps...@mattcorallo.com> wrote:
> >>
> >> Hmm, well I suppose consider this a feature request for
> >> sender_dependent_relay_transport_maps or sender_dependent_transport_maps :)
> >
> > No such feature fits into a single-key lookup design.
> >
> > You're looking to exempt specific sender (domains) from the recipient-based
> > nexthop of specific recipient domains. This is a multi-key transport
> > decision, and supporting this requires a radically different design.
> >
> > So the feature request is extremely unlikely to be actionable.
>
> Correct me if I'm wrong, but it should still be possible to have
> a sender-dependent lookup that happens before transport_maps or
> relay_transport_maps? Indeed, I understand that no multi-key lookup
> can occur, but the decision could be made first by an optional
> sender lookup, then by the recipient lookup, then the default, no?
If the sender address can override the routing, even if the recipient
would otherwise be delivered locally, then that would be a recipe
for mailer loops with the potential for mail explosions. This is
why we have sender_dependent overrides for default transports and
relay hosts, and avoid such stability problems.
Wietse
> In any case, I'll likely go with a second instance of postfix for now, but
> its a lot of additional complexity.
>
> Matt
>
