What's New: VSS in Windows Server 2008 R2 & Windows 7

Windows Server 2008 R2 and Windows 7 introduce the following changes to the Volume Shadow Copy Service.

New VSS Interfaces


New VSS Classes


New VSS Enumerations


New VSS Functions


Existing VSS Interface Modifications

IVssHardwareSnapshotProviderEx interface

Added method: ResyncLuns

VSS Event Tracing and Logging

Beginning with Windows Server 2008 R2 and Windows 7, you can use the VssTrace tool, the Logman tool, or the Tracelog tool to collect tracing information for the VSS infrastructure. For more information, see Using Tracing Tools with VSS.

LUN Resynchronization

In Windows Server 2008 R2 and Windows 7, VSS requesters can use a hardware shadow copy provider feature called LUN resynchronization (or "LUN resync"). This is a fast-recovery scheme that allows an application administrator to restore data from a shadow copy to the original logical unit number (LUN) or to a new LUN. The shadow copy can be a full clone or a differential shadow copy. In either case, at the end of the resync operation, the destination LUN will have the same contents as the shadow copy LUN. During the resync operation, the array performs a block-level copy from the shadow copy to the destination LUN. For more information, see the following:

Express Writers

In Windows Server 2008 R2 and Windows 7, the VSS express interface allows an application to register the location of its data files without implementing a VSS writer. For more information, see Volume Shadow Copy Service (VSS) Express Writers.

New VSS Writers

Windows Server 2008 R2 and Windows 7 introduce the following VSS writers:

  • Performance Counters Writer
  • Task Scheduler Writer
  • VSS Metadata Store Writer

These new writers are documented in In-Box VSS Writers.