Grid Considerations For Copy Export - IBM TS7700 Series User Manual

August 15, 2017

Grid Considerations for Copy Export

Copy export is supported in a Grid configuration, but there are several considerations regarding that support.
Support is provided starting with the 8.4.x.x code level.
The first has to do with how copy export is performed. In a Grid configuration, a copy export operation is
performed against an individual TS7700, not across all TS7700s. In setting up to use copy export in a Grid
you will need to plan for the following:
• Decide on which TS7700(s) in a Grid configuration is going to be used to export a specific set of data.
Although you can set up more than one TS7700 to export data, only the data from a single source
TS7700 can be used in the recovery process. You cannot merge copy exported volumes from more than
one source TS7700 in the recovery TS7700.
• For each specific set of data to export, define a management class name. On the TS7700 that will be
used to export that data, define a secondary physical volume pool for that management class name and
also make sure that you indicate that it is an export pool. Even though you will need to define the
management class name on all TS7700s in the Grid configuration, only specify the secondary physical
volume pool on the TS7700 that is to perform the export operation. Specifying it on the other TS7700s
in the Grid configuration will not interfere with the copy export operation, but it will be a waste of
physical volumes. The exception to this would be if you want one of the TS7700s in the Grid
configuration to have a second physical copy of the data in the event that the primary copies on other
TS7700s are not accessible.
• As you are defining the management class name for the data, also make sure that the TS7700 to perform
the export operation will have a copy policy specifying it is to have a copy.
• When the copy export operation is executed, the export list file volume must only be valid on the
TS7700 performing the operation. You will need to define a unique management class name to be used
for the export list file volume. For that management class name, you will need to define its copy policy
such that a copy is only on the TS7700 that is to perform the export operation. If the volser specified for
the export list file volume when the export operation is initiated is resident on more than one TS7700,
the copy export operation will fail.
• On the TS7700 on which a copy export operation is initiated, do not set items of Copy Policy Override
checked through the management interface panel. Activating Copy Policy Override, allows a copy of
export list volume created on the TS7700 regardless of the management class setting and causes copy
export failure. For instance, assuming three clusters c0, c1, c2 exists in a grid configuration. A copy
export with the export list volume EXP000 is initiated from a host connected to the c0, and the copy
export runs on the c2. The copy mode of EXP000 must be [N,N,D] or [N,N,R] indicating that the only
copy of EXP000 exists on c2. If Copy Policy Override is actived on the c0 and the copy export is
initiated from the host attached to c0, a copy of EXP000 is created both on the c0 and c1. Grid detects
that a copy of EXP000 exists on 2 clusters (co and c2) and does not start the copy export. Copy export
fails
For example, assume that the TS7700 that is to perform the copy export operation is cluster 1. The pool on
that cluster to export is pool 8. You would need to set up a management class for the data that is to be
exported such that it will have a copy on cluster 1 and a secondary copy in pool 8. To ensure the data is on
that cluster and is consistent with the close of the logical volume, you would want to have a copy policy of
Rewind/Unload (RUN). Define a management class, for example, of MCCEDATA, on cluster 1 as follows:
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