Composite data source

I do not believe the proposed configuration would work in the environment.  The Shared disk data source and the Mirror Data source both use the VincaMV filter driver to block access to the partition.  Using both data sources on the same partition may cause a conflict in the driver and potentially cause unexpected behavior with one of the data sources.

The concept of this configuration may not work either because there is no replication mechanism to Node C when the Resource group is running on Node A.  In the proposed configuration the Mirror Data source only replicates when the data source is attached to node B.  If the resource group is running on node A then it will only attach the shared disk and the C node partition will not be updated.

Typically the Composite data source is used with a local Shared Disk or mirror data source between nodes A and B.  A RepliStor data source will be used to replicate the data to node C and will only be enabled on the node which is currently running the local shared disk or mirror data source.  Here is an overview of the Composite data source:

Node A to Node B = Shared or mirror Data Source
Node A to Node C = RepliStor Data Source
Node B to Node C = RepliStor Data Source

So when the Shared Disk is attached to Node A it will also enable the RepliStor data source from node A to Node C.  When you failover to node B it will then enable the RepliStor Data source from node B to Node c.  With this configuration it will always replicate to the DR site regardless of which local node is running the resource group.

Please view the EMC AutoStart administrator's guide as the data source requires the configuration of environmental variables on top of selecting the individual data sources.  I hope this helps with your Composite data source configuration.