IBM TotalStorage 3494 Tape Library, Руководство оператора

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Operations
The 3494 Tape Library performs host-initiated and stand alone operations.
Host-Initiated Operations
The following are host-initiated operations:
v Mount operations
v
Demount operations
v Eject operations
v
Audit operations
v
Export operations
v Import operations
Mount Operations
Host-initiated mount operations result in the 3494 Tape Library performing either a
physical or logical mount. The drive address to which the mount is issued
determines whether the host-initiated mount is physical or logical. When the
mount is issued to a tape drive address within a VTS or TS7700 Virtualization
Engine, the 3494 Tape Library performs a logical mount operation. For all other
tape drive addresses, the 3494 Tape Library performs a physical mount operation.
The Library Manager directs the cartridge accessor to move a physical volume
from its current location to the specified tape drive. The following are the types of
mount operations:
Mount specific
The mount request specifies the specific volser to be mounted.
Mount from category
The volser to be mounted is picked from the specified category in the
mount request.
Physical mount operations result in a volume being placed in a drive and the drive
loading the volume. The cartridge accessor performs physical mounts.
The VTS or TS7700 Virtualization Engine performs mounts for logical volumes.
They may or may not require a physical mount.
Logical mount operations result in a virtual volume being made available to the
host through a virtual tape drive. The following are the types of logical mount
operations:
Fast Ready Mount
The host requested a category mount, and the category was designated as
a “Fast Ready” category. This type of mount selects a volser from the
specified category and logically mounts it on the virtual tape drive. An
odd or even volser selection algorithm is used to maximize VTS or TS7700
Virtualization Engine performance. No recall of the data from the previous
use of the volser from physical tape is performed.
Cache Mount
The host requested a specific volser, and the virtual volume for that volser
is resident in the tape volume cache. No recall of data from a physical tape
is performed.
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3494 Tape Library Operator Guide