I have a need to map some destination domains to a specific smtp nexthop, but need to override that nexthop on a
sender_dependent basis. I've tried a few things and all with no luck:
* transport_maps specifying the nexthop can't be overridden at all, it seems (and doesn't support sender_dependent
matching),
* putting the specified destination domains in relay_domains (and stopping relay to them via smtpd_relay_restrictions)
but there doesn't seem to be a way to override relay_transport on a sender_dependent way
* relayhost-based stuff doesn't seem to be an option as I don't want to change the delivery of mail that isn't either
from one of the sender_dependent rules or to one of the specified domains.
Am I missing something or is there some way to do a custom rewrite engine?
Thanks,
Matt