Perhaps the OP should explain the *actual* problem he's trying to
solve, rather than the artificial goal of routing inbound mail
via a second SMTP hop, while outbound mail goes direct.
End game goals:
Server 1 is the MX server to accept mail for domain. It should not be
tasked with submissions, relays, etc. Keep it available for one purpose
only for balancing purposes.
Server 2 is to cater to the end user, to handle their needs for their
email client. Checking mail (imap) and sending messages (submission)
from their email client. In my mind, postfix has no need to even be on
server 2 except for the fact dovecot does not prevent address spoofing
on submission service.
From an administrative and maintenance perspective, both of these
servers have near identical setup. The only difference is on server one
i #comment out the submission service and on server two i #comment out
the smtp service.
The issue im trying to avoid is that when postfix/submission accepts a
message meant for another user on the same domain, it delivers it
directly to maildir and does not put that message through the same
filters, milters, policy servers as if the message was accepted by
smtp:25. For one example if j...@example.com wants to blacklist
j...@example.com it does no good as submission will drop jack's email
right into jill's maildir anyways.
Now on the two server setup, this is solved removing the
virtual_mailbox_domains on server two. Great i can live with that
solution. But in my quest to KISS everything, it would be great if there
was something *that* simple i can also apply to a single mail server
setup. This is why i was hoping something like adding a single -o to
submission would change the behavior for just those emails submitted via
submission. I now know this is not how postfix is designed to work. FYI,
i have both, a single server postfix for one domain, and a multi server
postfix for a second domain.
