IBM System Storage TS3500, Введение и руководство по планированию

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Dynamic partitioning
The following topics explain dynamic partitioning. Dynamic partitioning in the
TS3500 Tape Library is comprised of storage slot pooling and flexible drive
assignment.
Storage slot pooling
When enabled in the TS3500 Tape Library, the Advanced Library Management
System (ALMS) allows logical libraries to be added or deleted without disrupting
operation. All storage slots are pooled (available on a first-come, first-served basis)
to each logical library based on cartridge insert operations. They are a shared
resource such that changes to the capacity allocation for each logical library can
occur without downtime or administrator involvement. The minimum logical
library simply has a name and can be thought of as a file folder that has no
contents. Drives can be placed in the file folder by using the Drive Assignment
screen of the Tape Library Specialist Web interface. Cartridges can also be placed in
the file folder, based on their volume serial (VOLSER) numbers and by using one
of the following methods (in priority order):
v
Migration of static partitioning to dynamic partitioning (requires Web
enablement of ALMS)
v Cartridge assignment policy (automatic at the time of insertion)
v
Software application move from the I/O station (based on the source application
that issued the command)
v
Manual assignment by an operator using the Tape Library Specialist Web
interface
For information about migrating to dynamic partitioning and manually assigning
cartridges to a logical library, refer to the
IBM System Storage TS3500 Tape Library
with ALMS Operator Guide .
The primary and backup copies of VOLSER assignment and physical location of
cartridges are stored in non-volatile random access memory (NVRAM).
Flexible drive assignment
After you enable the Advanced Library Management System (ALMS) in the TS3500
Tape Library, you can assign drives to a logical library by using the Drive
Assignment screen of the Tape Library Specialist Web interface. You can assign a
drive to be shared by multiple logical libraries (for example, a drive used for a
once-a-month job or as a temporary replacement for a failed drive). Thus, each
logical library can consist of dedicated drives and shared drives. Each logical
library maps a drive element address to the locations of both dedicated and shared
drives. This allows multiple applications to be pre-configured to quickly use a
shared drive in the future. After you pre-configure the applications for future drive
usage, you must take each shared drive offline at all but one of the applications
that have access to it. Otherwise, an application may attempt to use a drive that is
in use by another application. This may cause failed backup jobs. Also, most
applications consider the symptoms of a drive already in use to be an error that is
reported as such.
The Drive Assignment Web screen supports the following capabilities which are
not disruptive to other logical libraries:
v
Assign the drive
v
Remove the drive assignment
v
Reassign the drive
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IBM System Storage TS3500 Tape Library with ALMS: Introduction and Planning Guide