Topics | How To | Related Topics
When using VSS, write operations on the data being backed up can continue while these open files are copied and backed up, eliminating locked file conditions.
VSS can be enabled for backups of local volumes in both clustered and non-clustered environments. If the operating system fails to create a shadow copy of the data a traditional backup of the data will be performed, and a corresponding message will appear in the Event Viewer.
During a VSS backup, the free space needed on a volume for the shadow copy is related to the duration of the backup and the amount changes being made to the data objects (files, databases) that are being backed up. VSS snapshots capture and copy disk blocks that are being changed by other processes while the backup for a particular object is running. If the backup runs longer, or there is a lot of disk activity (files or databases being changed), this would cause VSS to copy more data blocks and therefore, use more disk space.
Microsoft Volume Shadow Service is the default, and only supported VSS software provider. The VSS software provider takes a snapshot of the source volume, database or file, which is then used to create backups or QR Volumes (when used with the Quick Recovery Agent).
VSS can be enabled for backups of local NTFS volumes. If selected, the following will automatically occur:
Before selecting the Use VSS option with SQL, you should review the VSS-related items in this agent's Restore Considerations.
When the SQL Server iDataAgent is installed on a CommServe computer and you are running VSS-enabled backups, System database backup jobs convert to VDI backups.
Refer to Microsoft documentation for information on how to enable SQL Writer in SQL Server 2005/2008.
The following must be done before using VSS.