3yrs is indeed a long time. I'm happy that it's working out for you.
If you want to use the relay_domain and transport files from your older boxes, you'd have to edit /etc/postfix/main.cf and make it look like:
relay_domains = hash:/etc/postfix/relay_domains
transport_maps = hash:/etc/postfix/transports
Make sure to edit those files accordingly and postmap them.
I've gone with a much easier approach to setting up the Snake,
almost everything can be done through Baruwa. The mysql setup is
the best way to do it now, since all the records can be created through
the frontend with the exception of relay_recipients. Of course you can
always use the system the old school way, the way you've been doing it
without any issues. You just have to make sure main.cf is set up
appropriately and also the associated files.
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