Copy policy override

Use this page to override local copy and I/O policies for a given IBM® TS7700 Cluster.

For the selected cluster, you can tailor copy policies to override certain copy or I/O operations. Select the check box next to one or more of the following settings to specify a policy override:
Prefer local cache for scratch mount requests
When this setting is selected, a scratch mount selects the local tape volume cache if:
  1. The Copy Mode field defined by the management class for the mount has a value other than No Copy defined for the local cluster,
  2. The Copy Mode field defined for the local cluster is not Deferred when one or more peer clusters are defined as Rewind Unload (RUN), AND
  3. The local cluster is not in a degraded state. Examples of a degraded state include:
    • Out of cache resources
    • Out of physical scratch
Note: The cluster is not required to have a valid copy of the data to enable this override setting.
Prefer local cache for private mount requests
This override causes the local cluster to satisfy the mount request if:
  1. The cluster is available, AND
  2. The local cluster has a valid copy of the data, even if that data is only resident on physical tape
If the local cluster does not have a valid copy of the data, then default cluster selection criteria apply.
Force volumes mounted on this cluster to be copied to the local cache
When this setting is selected for a non-scratch mount, a copy operation is performed on the local cluster as part of the mount processing.
When this setting is selected for a scratch mount, the copy consistency point on the specified management class is overridden for the cluster with a value of Rewind/Unload. This override does not change the definition of the management class, but influences the replication policy.
Allow fewer RUN consistent copies before reporting RUN command complete
When this setting is selected, the maximum number of Rewind/Unload (RUN) copies, including the source, is determined by the value entered at Number of required RUN consistent copies including the source copy. This value must be consistent before the RUN operation completes.
If this option is not selected, the management class definitions are used explicitly. Thus, the number of RUN copies can be from one to the number of clusters in the grid configuration or the total number of clusters configured with a RUN copy consistency point.
Ignore cache preference groups for copy priority
If this option is selected, copy operations ignore the cache preference group when determining priority of volumes copied to other clusters.
Note: These settings override default TS7700 behavior and can be different for every cluster in a grid.
To change any of the settings on this page:
  1. Check or clear the box next to the setting you want to change.
  2. If you enable Allow fewer RUN consistent copies before reporting RUN command complete, you can alter the value for Number of required RUN consistent copies including the source copy.
  3. Click the Submit Changes button.