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A parallel group is a group composed of the resources that can be run at more than one node at the same time.
A parallel group does not failover.In general, the resource containing applications made of cluster is online at the active node and offline at the standby node.
However, if you use a parallel group, you can start, monitor or terminate and stop the designated application at the both nodes.
For instance, if the both nodes operate the backup software and you register it as the resource managed in a cluster, you can run the backup software at the both nodes at the same time. (But, the application should be run at multiple nodes in parallel.)
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