Dell MD3220, MD3200 owner manual Guidelines for Creating Snapshot Schedules, 141

Friday, at a time between the end of the work day and 11PM. Do not select an end date. Apply the same schedule to the second virtual disk, then map the two snapshot virtual disks to your backup host server and perform your regular backup procedures. Remember to unmap the two resulting snapshot virtual disks before the next scheduled snapshot begins. If the snapshot virtual disks are not unmapped, the storage array does not perform the next scheduled snapshot operation in order to avoid data corruption.

Scheduled snapshots are also valuable in the event of a data loss. For example, if you back up your data at the end of every work day and keep hourly snapshots from 8AM to 5PM, data can be recovered from the snapshots in windows smaller than one hour. To accomplish this type of rapid recovery, create a schedule that contains a start time of 8AM and an end time of 5PM, then select 10 snapshots per day on Monday through Friday with no end date.

For more information on creating snapshot virtual disk schedules, see the following sections on creating snapshots.

Guidelines for Creating Snapshot Schedules

Certain guidelines apply when creating snapshot virtual disk schedules:

•Scheduled virtual disk snapshot operations do not occur if:

–The snapshot virtual disk is mapped

–The storage array is offline or powered off

–The snapshot virtual disk is in use as a source virtual disk during a Virtual Disk Copy operation

–A copy operation is Pending or In progress

•Deleting a snapshot virtual disk that contains a schedule also deletes the schedule

•Snapshot schedules are stored in the configuration database on the storage array. The Management Station does not need to be running for scheduled snapshot operations to occur.

•Snapshot schedules can be created when the snapshot virtual disk is initially created or can be added to existing snapshot virtual disks.

Configuration: Premium Feature—Snapshot Virtual Disks

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