Creating a synchronous copy relationship between volumes in different clustered systems

The IBMTSSVC_StorageConfigurationService class provides the methods for creating a synchronous copy relationship between a source IBMTSSVC_StorageVolume instance and a target IBMTSSVC_RemoteStorageVolume instance that belongs to different IBMTSSVC_Cluster instances.

1. Identify an IBMTSSVC_Cluster instance as the source clustered system for the preferred synchronous copy relationship.
2. Obtain the reference (CIMObjectPath) of the IBMTSSVC_StorageConfigurationService instance that is associated with the source clustered system.
3. Identify the IBMTSSVC_RemoteCluster on which you want the synchronous copy to reside by traversing the IBMTSSVC_RemotePartnership association.
4. Create a remote clustered system partnership by invoking the IBMTSSVC_CascadingAllocationService.Allocate() method with the following parameter specifications:
   1. Set RemoteCluster to the reference (CIMObjectPath) of the IBMTSSVC_RemoteCluster instance.
   2. Optionally set Bandwidth to the preferred bandwidth in megabytes (MB).

   Make sure to issue the method from both the source and candidate clustered systems to establish a fully configured partnership; otherwise, the synchronous copy relationship cannot be established.

5. Select an IBMTSSVC_StorageVolume as the source volume from the source IBMTSSVC_Cluster.
6. Select an IBMTSSVC_CandidateVolume as the target volume from the IBMTSSVC_RemoteCluster. To determine a candidate volume, use the IBMTSSVC_CopyCandidate association from the source volume.
   Note: IBMTSSVC_StorageVolume instances on the remote clustered system are seen on the local clustered system as a IBMTSSVC_CandidateVolume instance.
7. Invoke the IBMTSSVC_StorageConfigurationService.AttachReplica() method with the following parameter specifications:
   1. Set SourceElement to the reference (CIMObjectPath) of the source IBMTSSVC_StorageVolume instance.
   2. Set TargetElement to the reference (CIMObjectPath) of the target IBMTSSVC_CandidateVolume.
   3. Optionally set ElementName to the name of the synchronization.
   4. Set CopyType to 3 for Synchronous, and 2 for Asynchronous.