Fundamental to the device server concept is the notion of a device. Every device server which wants to run has to be declared in the resource database so that it has an entry in the NAMES table. If the device server is not going to export any devices then a dummy device name has to be given.
The resource database is served by a database server (of course) called dbm_server. The database is based on the GNU dbm routines. Each database table is stored in a separate dbm ``database'' and consists of two files TABLE.pag and TABLE.dir where TABLE is the name of the table. Tables are specified in an environment variable called $DBTABLES.