DB files are in ibd format

I assume you’re aware that MariaDB isn’t supported for Ghost, right?

Docs here:

Recent discussion about MariaDB non-support (also links an older thread): Does Ghost work with MariaDB - #7 by vikaspotluri123

I’m not sure you’re going to find the expertise you’re looking for here, so you may want to cross post your question in a MariaDB forum also.