White, Daniel E. (GSFC-770.0)[NICS]:
> Server 1 - MTA - Relay only - Postfix, Amavis, Spamassassin, Clam AV - No
> local or virtual mail users on this server.
> Server 2 - MDA - Where the Mailboxes Live - Postfix, Dovecot, RoundCube,
> PostfixAdmin - All mail users are virtual.
>
> Mail sent to the MTA wants to deliver to a local user on MTA rather
> than relaying to MDA. We get the ??User unknown in local recipient
> table? error, which makes sense. What are the configuration
> settings that we have obviously missed that will send the mail to
> MDA and NOT try to deliver mail locally on MTA ?
Postfix will deliver a domain locally when it matches mydestination.
So don't do that.
Wietse