Typical VSS backup process

A typical backup using SnapManager for Microsoft Exchange, Microsoft Exchange 2003 or 2007, and the Data ONTAP VSS Hardware Provider is outlined in the following process.

1. SnapManager determines which LUNs it wants to capture and makes sure that Exchange 2003 or Exchange 2007 is present as a valid writer.
2. SnapManager initiates the shadow copy process.
3. VSS informs Exchange and the Data ONTAP VSS Hardware Provider that a shadow copy is starting. Exchange stops writing to disk.
4. VSS ensures that NTFS is in a consistent state.
5. VSS requests the Data ONTAP VSS Hardware Provider to create a shadow copy.
6. The Data ONTAP VSS Hardware Provider requests SnapDrive to create a Snapshot copy of the storage system volume that contains the specified LUN.
7. SnapDrive requests the storage system to create a Snapshot copy of the specified volume.
8. When the shadow copy is complete, VSS returns NTFS to a normal state and informs Exchange that it can resume disk writes.
9. VSS manages the shadow copy of the LUN based on the attributes specified by the requestor. For example, VSS could mount the LUN in a Snapshot copy. In a case, however, in which SnapManager is the requestor, SnapManager tells VSS to forget about the shadow copy it just created. This enables SnapManager to have complete control of the Snapshot copy.