HP B6960-90078 manual

Backup

Backing Up Windows Systems

The advantages of the VSS filesystem backup are the following:

•A computer can be backed up while applications and services are running. Therefore, the applications can continue writing data to the volume during a backup.

•Open files are no longer skipped during the backup process, because they appear closed on the shadow copy volume at the time of the shadow copy creation.

•Backups can be performed at any time without locking out users.

•There is little or no impact on performance of the application system during the backup process.

For VSS filesystem backup related options, refer to “Using Backup

Options” on page 225. Also refer to the HP OpenView Storage Data

Protector Concepts Guide for details on the VSS concepts.

Reparse Points Basically, reparse points are plain filesystem objects with a unique tag attached, known as a reparse point ID. The NTFS 3.x directories or files can contain a reparse point, which typically imitates the contents by directing to data from another location.

When Data Protector encounters reparse points, the reparse point IDs are not followed by default, what is also known as backing up raw reparse points. This affects the way you configure your backups:

✓If you configure a backup using Disk Delivery, all data will be backed up once.

✓If you back up filesystems or drives containing reparse points, ensure that the data pointed to by a reparse point gets backed up. For example, the Windows 2000/XP/Server 2003 directory junctions reparse points are not followed, so the junctions have to be backed up separately. SIS reparse points are exceptions.

The Single Instance Storage (SIS) service regularly checks the files on a disk. If the service detects several identical files, it replaces them with the reparse points and stores the data into a common repository. In this way, the disk space usage is reduced.

Reparse points let you mount logical volumes as disk drives. Data Protector treats the mounted volumes as though they were ordinary drives, so that they are visible as selectable objects for backup.

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