File System

In the file system persistency layer, each subfolder of your data folder is a database.

Each folder has the following files:

• schema.json - list of all tables, columns, keys and shards; is updated every time a shard is added or removed or the schema changes
• schema.json.old - fallback file for crash recovery
• [uuid]-[columnname] - the content of a column (in case the ENGINE is not MEMORY)
• [uuid].log - transaction log in case the ENGINE is LOGGED or SAFE

You can also use a Cluster Monitor for the File System persistency backend. The only thing you have to assure is that each node of the cluster points with -data to the same shared directory.