IBM TS7700 Series, Руководство пользователя

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August 15, 2017
© Copyright IBM Corporation, 2017 Page 11 of 117
9. Only one secondary physical volume pool can be specified per export operation and it must have been
previously defined as a copy export pool.
10. Specific logical volumes are not specified as part of a copy export operation, rather all valid logical
volumes on the physical volumes in the specified secondary pool will be considered for being exported.
After the first time copy export is performed for a pool, the logical volumes that will be exported are
only the ones for that pool that have been newly written or modified since the last export began. For
recovery, all exported physical volumes that still contain active data from a source TS7700 need to be
included as not all of the logical volumes created are going to be on the last set exported.
11. During execution, if the TS7700 determines that a physical volume assigned to the specified secondary
pool contains one or more primary logical volumes, that physical volume and any secondary logical
volume on it are excluded from the copy export operation.
12. Logical volumes are stacked on physical volumes managed by a TS7700. They are not directly readable
by a physical tape drive. They can only be accessed through a TS7700.
13. The primary copy of the logical volumes exported remains in the inventory of the TS7700 and Grid.
14. A physical volume written in a pre-TS7700 format cannot be exported. The Physical Volume Status
request of the BVIR function can be used to obtain information about the physical volumes in a pool.
Included in that information is the format the volume was written in. If any of the volumes are still in
the pre-TS7700 format, use the physical volume move function of the library manager to force a
conversion of the data on the volume to the TS7700 format. Also see the description in section
Copy
Export Operation , pre-execution checking for more details.
15. When a copy export operation is initiated, only those logical volumes assigned to the secondary pool
specified in the Export List File Volume that are resident on a physical volume of the pool or in the
cache of the TS7700 performing the export operation will be considered for export. For a Grid
configuration, if a logical volume is to be copied to the TS7700 that will be performing the copy export
operation, but that copy had not yet completed when the export is initiated, it will not be included in the
current export operation.
16. Logical volumes to be exported that are resident only in the cache and not mounted when the copy
export operation is initiated will be copied to stacked volume in the secondary pool as part of the copy
export operation.
17. Any logical volume assigned to the specified secondary pool in the TS7700 after the copy export
operation is initiated is not part of the export and will be written to a physical volume in the pool but
will not be exported. This includes host as well as copy sourced data.
18. To minimize the number of stacked volumes used for copy export, you should use the highest capacity
media and physical drive format that is compatible with the recovery TS7700. The number of concurrent
tape devices can be changed via Maximum Devices in pool properties setting. This can reduce the
number of concurrent tape devices that the TS7700 will use when copying data from cache to the
secondary copy pool used for copy export.
19. All copy exported volumes exported from a source TS7700 must be placed in a library for recovery.
The source TS7700 will limit the number of physical volumes that can be copy exported to
approximately 2000 to ensure that they will all fit into the receiving library. At code release level R1.6
and higher, the value can be changed to a maximum of 10000.
20. The recovery TS7700 must have physical tape drives that are capable of reading the physical volumes
from a source TS7700.