[Adoby]

I would recommend that you instead start with setting up a robust system to backup (and restore) your calibre library locally. Especially if you intend to store your library in a networked/shared/cloud folder.

You should also research what guarantees there are for the cloud storage service you want to use. Most likely you will find that there are very limited guarantees, if any, and that you are recommended to always have a local backup.

It could be a very good idea to set up your solution so that glitches, errors or lost files in the cloud or on other connected devices don't propagate automatically to the main local library.