On Thu, May 19, 2022 at 01:06:09PM +0200, Jan-Martin Raemer wrote: > /etc/postfix/transport: > user@domain smtp:[nondefault-relay.domain]:25 > user+ext@domain smtp:[nondefault-relay.domain]:25
Unsolicited advice, avoid per-user transport mappings, instead use virtual(5) rewriting to map special users to special domains. Route these domains to appropriate relays. This keeps the transport table small and simple. If the receiving relay needs to see the original address, a suitable reverse rewrite can be added via smtp_generic_maps. -- Viktor.