The subsystem device driver (SDD) for Windows® supports dynamic pathing for hosts that are running the Microsoft® Hyper-V operating system.
SDD supports dynamic pathing when you add more paths to an existing VDisk and when you present a new VDisk to the host. No user intervention is required, other than what is normal for a new device discovery under the Windows operating system.
SDD uses a load-balancing policy and tries to equalize the load across all preferred paths. If preferred paths are available, SDD uses the path that has the least I/O at the time. If SDD finds no available preferred paths, it tries to balance the load across all the paths that it does find and uses the least-active nonpreferred path.