Simple. Setup the postfix transport settings in main.cf with mysql:/etc/postfix/mysql-transports.cf
Make sure you follow the guide on the postfix section.
Log into Baruwa as admin, or whatever your admin user is. Go to the settings tab and setup your account/domain info. Whatever you put into the mail host field will be your transport for whichever domain you're working with.
The query will pull the result in this format:
smtp:mail.example.com:25 if domain = domainA
Everything for postfix is handled via Baruwa now, so no need to edit postfix tables manually.
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