In addition to optical disk drives, OAM also can store the primary copy, or the backup copy, or both, of objects on tape volumes that can be mounted on these tape drives. OAM provides support for various IBM tape subsystems (stand-alone tape drives), the automated tape library dataserver (ATLDS), and the manual tape library (MTL).

Unlike optical drives, tape drives are not defined to the system through ISMF. The system allocates the tape drives to use to satisfy read and write requests of objects. The system relies on information from the ACS routines, and the location of the volume to be mounted to determine what device should be allocated to handle the request. If the volume is a library-resident volume (residing in an ATLDS or MTL), the system chooses a device to satisfy the request. If the volume resides outside of an ATLDS or MTL, the system allocates a stand-alone drive. The drive selected for use with a stand-alone tape depends on the TAPEUNITNAME associated with that tape in the TAPEVOL table row. For an MVS scratch tape (which has no TAPEVOL table row), the TAPEUNITNAME associated with the storage group to which the tape is assigned determines the type of stand-alone device which is allocated. See Table 1 for detailed information on all supported models.

Related reading: For more information concerning tape hardware configurations, and OAM’s role with the tape library dataservers and stand-alone tape drives, see z/OS DFSMS OAM Planning, Installation, and Storage Administration Guide for Tape Libraries.