IBM TotalStorage 3494 Tape Library, Operator'S Manual

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Storage Management of the Tape Volume Cache
Storage management software manages the contents of the tape volume cache.
Virtual tape volumes are copied from the tape volume cache to physical tape when
the virtual volume has been closed, and they are recalled from tape to the tape
volume cache when they are again requested to be mounted. The storage
management software stacks multiple migrated files onto a tape, thereby using the
full physical tape storage capacity. DFSMS policy management provides users with
the ability to control tape volume cache preferences for the retention of virtual
volumes.
VTS Export and Import Overview
The following sections provide an overview of VTS Export and Import operations.
Export and Import Operations
Note: In a PtP VTS configuration, the Export and Import functions of FC 4000,
Advanced Function, or FC 4001-4004, Advanced Policy Management, will be
disabled.
The Export and Import operations provide a way to move logical volumes out of a
VTS to physical cartridges called Exported Stacked Volumes and to return them to
the same VTS or move them to another VTS. Lists of volumes for Export or Import
operations are provided to a VTS on logical volumes called the Export List Volume
or the Import List Volume, which are resident in the VTS. The Status File on the
Export or Import List Volume provides status for each logical volume being
processed. See Appendix B,
″
VTS Export and Import Advanced Function,
″
for
information about preparing the Export or Import List Volume.
An emergency copy of a logical volume may be made by the VTS Exported
Volume Read Utility (provided by DITTO/ESA for MVS) from an Exported
Stacked Volume using a native 3590 B1A, E1A, or H1A tape drive or 3592 E05 or
J1A tape drive in the VTS. The J -, K -, JA -, or JJ -type Exported Stacked Volume
must not be inserted into a 3494 Tape Library having a VTS with a volser range
that allows the cartridge to become a VTS Stacked Volume and be rewritten. Also,
adding VTS Stacked Volumes to your tape management system inventory can help
prevent inadvertent use of an Exported Stacked Volume.
Note: Media type JB is not supported with VTS.
Import
The Import operation allows logical volumes that are stored on physical Exported
Stacked Volumes to become logical volumes within a VTS. A specific volume or all
volumes may be imported from Exported Stacked Volumes that have been entered
into a 3494 Tape Library through the convenience I/O station and have been
moved to the Import category by an operator at the Library Manager console. Host
console messages provide status on progress and completion of the Import
operation.
Export
The Export operation allows data on logical volumes in a VTS to be removed from
the VTS onto physical Exported Stacked Volumes. The list of volumes to be
exported and a destination for each volume is provided by the host operator or
tape management system. Logical volumes with the same destination are grouped
on the same Exported Stacked Volume. This physical volume is then moved into a
category that allows an operator at the Library Manager console to eject the
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3494 Tape Library Operator Guide