HP B6960-96035 - Manual (Page 294)

writers, and backup and restore functionality. For detailed information on the
integration, see the HP Data Protector integration guide.
VSS backup
In case of VSS-aware writers’ backup, the consistency of data is provided at writer
level and does not depend on the backup application. Data Protector follows the
requirements provided by the writers when selecting what to back up.
During the backup of VSS-aware writers, Data Protector does not communicate with
each writer individually, but through the VSS interface. It uses the VSS integration
agent to connect the Volume Shadow Copy service, which coordinates the backup
process. VSS provides Data Protector with the writer-related metadata necessary for
performing a consistent backup and restore. Data Protector examines this data and
identifies the volumes to be backed up. Data Protector then requests VSS to create
a shadow copy of the specified volumes.
NOTE:
A Writer Metadata Document (WMD) is metadata provided by each writer. Writers
identify themselves by the metadata and instruct the backup application what to back
up and how to restore the data. Data Protector therefore follows the requirements provided
by the writer when selecting the volumes to be backed up and the restore method.
Volume Shadow Copy service synchronizes the writers and providers. After a backup
shadow copy is created, VSS communicates this information to Data Protector. Data
Protector performs a backup from the shadow copy volume to the media and then
notifies VSS that the shadow copy can be released.
VSS restore
VSS integration restore refers to the restore of data which was backed up using the
Volume Shadow Copy service and a writer. During the restore procedure, Volume
Shadow Copy service coordinates communication between Data Protector and the
writers.
When restoring VSS-aware writers, Data Protector first restores all the relevant
metadata to identify the backup components and to determine the restore method.
It then connects to the Volume Shadow Copy service and declares that the restore is
about to begin. VSS coordinates the writers’ activities during the restore. After Data
Protector has successfully restored the data, VSS informs the writers that the restore
has been completed and the writers can access the restored data and start their
internal processing.
Microsoft Volume Shadow Copy service 294