IBM Tape Library Magstar 3494, Руководство оператора

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Operations
The 3494 performs host-initiated and stand-alone operations.
Host-Initiated Operations
The following are host-initiated operations:
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Mount operations
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Demount operations
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Eject operations
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Audit operations
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Import operations
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Export operations
Mount Operations
Host-initiated mount operations result in either a physical or logical mount being
performed by the library. Whether the host-initiated mount is physical or logical is
determined by the drive address to which the mount is issued. When issued to a
drive address within a Virtual Tape Server, the library performs a logical mount
operation. For all other drive addresses, a physical mount operation is performed.
The library manager directs the cartridge accessor to move a physical volume from
its current location to the specified drive. The following are types of mount
operations:
Mount specific
The specific volser to be mounted is specified in the mount request.
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 loaded by
the drive. Physical mounts are performed by the cartridge accessor.
Mounts for logical volumes are performed by the Virtual Tape Server. 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. 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/even volser selection algorithm is used to maximize VTS performance.
No recall of the data from the prior 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.
Chapter 3. Operational Characteristics
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