Each tape or disk in a Removable Storage system has a state associated with it that determines the operations that can be performed with the media When media are inserted into a library, Removable Storage uses the on-media identifier or bar code to determine its state.
There are two sets of media states that govern media movement and usage by Removable Storage: physical states and side states.
The physical states identify operations performed that involve media location or movement. There are five possible physical states:
Tape or disk is currently in a storage slot in an automated library or is shelved offline.
Tape or disk is in the process of being moved.
Tape or disk is mounted in a drive and data is available to be read or written.
Tape or disk is mounted in a drive but data is not yet available to be read or written.
Tape or disk has been dismounted and is ready to be removed from a drive.
A tape or disk side is where actual information is stored. Side states identify operations performed that involve media usage rather than location or movement. There are nine possible side states:
Side is reserved for use by an application. The side is not available to any other application.
Side is currently available for use by an application.
Side is in use but cannot be used for write operations. The side is full.
Side is no longer available for use, as it has reached its allocation maximum.
Side's label type is recognized but its label ID is not recognized by Removable Storage.
The media type of the side is not compatible with the library. The tape or disk should be removed from the library.
Side is unavailable for allocation except by a single application. This applies only to two-sided media where one side has already been allocated.
Side has been placed in a free media pool but does not yet have a free media label. This is a temporary state.
Side's label type and label ID are not recognized by Removable Storage.
There is a relationship between side states and media pools: Import media pools can only hold media sides in the imported state. Unrecognized media pools can only hold media sides that are in the unrecognized state. Free media pools can only hold media sides that are in the available (and transitional unprepared) state.