Requirement is that volume creation should not wait till required disk partition are formatted.  Bring up the volume as earlier as possible and attach those partitions on the fly upon format completion.  Flow would be

Create Volume -> Input volume name, type, nfs/cifs reexports, volume access control and server selection on advanced mode (In default mode all servers are selected). Formatting data partitions of server will be started in background if needed and bring up volume with whichever data partitions are available and add other partitions dynamically upon format completion.

Requirement: Detect new disk being added and prompt user to start formatting