@brunoamaral You should not use H2 in production. Doesn't matter where to store it. Don't use it.
https://www.metabase.com/docs/latest/operations-guide/migrating-from-h2.html
I don't know if you have Postgres running somewhere else or not, but that has more to do with how you run your network than anything specific to Metabase.
Here's an example: https://github.com/metabase/metabase/issues/8401#issuecomment-460182635