Two vitual machines under single control panel

Hi

Is it possible to have two different instances of virtual machines, one for app layer and web server, the other only for database? And manage the database through one control panel?

When I try to add a database, under database servers, I only have localhost.

-------------
I found the solution to add database servers. Now if I install MariaDB or MySQL on the other instance manually, I'm good to go?

Does Plesk come with MariaDB pre installed? What if I install MySQL on the other server?