Breaking Shadow Copies

A requester can break a shadow copy set by using the IVssBackupComponents::BreakSnapshotSet or IVssBackupComponentsEx2::BreakSnapshotSetEx method.

A broken shadow copy is a volume that contains a shadow copy that is no longer managed by VSS. Breaking a shadow copy has meaning only if the shadow copy's provider is a hardware provider. This is because only hardware providers can implement a shadow copy as an actual volume with a life cycle independent of VSS. If VSS does not manage such a volume, it still is available.

Software providers maintain shadow copies only while involved in VSS operations. For that reason, breaking a shadow copy has no meaning for software providers.

If the shadow copy was managed by a hardware provider, the requester must import the shadow copy before calling BreakSnapshotSet or BreakSnapshotSetEx. In case of non-transportable (created by a hardware provider) shadow copies, they are imported implicitly as part of the IVssBackupComponents::DoSnapshotSet call.

After the requester has called BreakSnapshotSet or BreakSnapshotSetEx, the shadow copy set is still accessible via its device objects or other access paths, but it is no longer a shadow copy set. It can be managed as one or more LUNs by using the Virtual Disk Service (VDS) COM interfaces. Using VDS, a requester can convert the LUNs to read/write, mount them with drive letters, or mask/unmask them to other computers. See the VDS API documentation for more information.