What do I need to do in order to serve config entities from Mongo and cache from Redis database backends?
So basically: a) how do I tell Drupal that I want to use different db backend for certain tables? b) what is needed in regard to drivers for those database backends? Are they available?
This is similar to How can I save/load an entity from a different database?How can I save/load an entity from a different database? but in this case I am interested in entirely different db backend + I want to include also non-entity tables so that annotation approach is not working for me.