Since the first few releases, GeoServer stores configuration data in a folder. This is the default way to persist information and is also the most used method. It allows you to configure a cluster configuration, with more than one GeoServer instance pointing at the same directory. In order to avoid data corruption, you just have to disable the integrated GeoWebCache and carefully avoid editing configuration from more than one GeoServer admin interface at the same time.
Note
For more information about how to configure GeoServer to run multiple instances in parallel, refer to my previous book, GeoServer's Beginners Guide, Packt Publishing.
Are you wondering whether there is a way to store configuration data in an RDBMS? Indeed, there is one option—a community module that you may add to your installation.
The JDBCConfig module lets you use a relational database, such as PostgreSQL, to store GeoServer configurations.