Abstract: This file server system appears to the host computer to be a plurality of data storage devices which are directly addressable by the host computer using the native data management and access structures of the host computer. The file server however is an intelligent data storage subsystem that defines, manages and accesses synchronized sets of data and maintains these synchronized sets of data external from the host computer system's data management facilities in a manner that is completely transparent to the host computer. This is accomplished by the use of the snapshot application data group that extends the traditional sequential data set processing concept of generation data groups.

Abstract: The automated library system stores and retrieves media cartridges for an associated plurality of media drives. Within this system, a virtual robot is implemented to create multiple virtual media libraries within the single automated cartridge library system. This capability enables the use of a plurality of types of media within the single automated cartridge library and a corresponding plurality of drive elements within the library. Thus, each drive element has associated therewith a number of object storage locations within the library which contain media of a form and content that matches the drive element. The automated cartridge library system manages the correspondence between object storage location, media type, designated drive element in an automated manner such that the single library appears to the user as multiple independent libraries.