150 Configuration: Premium Feature—Snapshot Virtual Disksrepository uses less disk space than a full physical copy, because the only datablocks that are stored in the snapshot repository virtual disk are those thathave changed since the time of the snapshot.When you create a snapshot virtual disk, specify its location, capacity,schedule, and other parameters. You can disable or delete the snapshot virtualdisk when it is not required. If you disable a snapshot virtual disk, you can re-create and reuse it the next time you perform a backup. For moreinformation, see "Disabling a Snapshot Virtual Disk" on page 165. If youdelete a snapshot virtual disk, you also delete the associated snapshotrepository virtual disk.NOTE: Deleting a snapshot does not affect data on the source virtual disk.NOTE: The following host preparation sections also apply when using the snapshotfeature through the CLI interface.Scheduling a Snapshot Virtual DiskWhen you create a snapshot virtual disk, you can choose whether thesnapshot is created immediately or is created according to a schedule that youdetermine. This schedule can be a one-time snapshot creation or an ongoingsnapshot creation that occurs at regularly occurring intervals. If a schedule isnot specified, the snapshot virtual disk creation happens immediately uponexecution of the command.A schedule can be specified when a snapshot virtual disk is first created, or itcan be added to an existing snapshot virtual disk at any time. One scheduleper snapshot virtual disk is supported.Common Reasons for Scheduling a Snapshot Virtual DiskScheduling a snapshot virtual disk can serve multiple purposes across a datastorage environment. Most common uses of a snapshot scheduler are:• Data backups• Rapid recovery from a data loss eventA scheduled data backup can protect against data loss on a regular,unmonitored basis. For example, if an application stores business-critical dataon two virtual disks in the storage array, you may choose to perform anautomatic backup every day.
