Outbound Smarthosting



If I understand correctly from this comment on another post, I can change the relayhost in postfix’s main.cf to use an outbound messaging gateway and the MIAB won’t override my config (until potentially an upgrade), correct?

I would like to use my existing Proofpoint infrastructure for outbound while moving to a self-hosted server.


What are you looking to do exactly? If you just need a spam filter, that’s simple enough to setup.

If you need outbound email while moving servers, that’s not possible with smarthosts. The server / services need to be online in order to use a smarthost.


I added sender_dependent_relayhost_maps = hash:/etc/postfix/bysender.cf to my postfix main.cf and then added to that bysender.cf fille domain.com [outbound.smarthost.com] so that it routes the domain via the smarthost.

My only concern is that I read that MIAB restores main.cf to original defaults during “cleanup” and that edit may be wiped. But in the meantime, that config works perfectly