Steve,
I'm referring to Postfix specific records, not Mailman records which are not the topic of conversation here.
Presently, Mailman creates two files under "/opt/mailman/mm/var/data"...
"postfix_lmtp" which is a "transport_maps" table "postfix_domains" which is a "relay_domains" table
The instructions in the docs says to set these up as "hash" table entries in Postfix so that when they're updated by MM Postfix references get updated accordingly.
What I'm doing is, converting the "hash tables" to MariaDB tables stored in a Postfix specific database.
Two primary objectives are intended with this updated architecture design...
allow management of Postfix tables through my web UI
Offer future scalability whereby the database for MM and Postfix amongst other things may get placed on a separate node, and/or setup in a Master-Master mirror cluster.
*** On a segway, but related to the overall goal... I'm adding OpenDKIM management into my admin UI, which also is tied to a MariaDB database for key signing tasks and management. For the same reasons above, this is why I'm moving from files to databases. ***