If OntoBroker is not running, you can backup the H2 database simply by copying all of the database files. In fact it is even enough to backup the <dbname>.data.db file. However, in this case H2 will regenerate the database index file <dbname>.index.db containing all indices during the next startup of OntoBroker. Recreating indices may take some time, depending on the database size and computing power of your computer (typically a few minutes per GB).