Rotating Drives Approach

What is Backup Rotation?

The Rotating Drives strategy consists of regularly copying data to an external media device, which is mounted each time the backup job is performed. These devices are subsequently swapped and contain the full data copy, so rotation helps to reflect up-to-date changes. When the drive with the old version of data is used for a backup again, all outdated blocks are overwritten.

This approach was first applied to the tape data repositories, where device rotation was the only way possible to keep data hot and provide versioning.

Nowadays, there are cloud storages and a number of local and offsite repository solutions that can substitute for tape media. But despite the decline of the parent technology, the rotating drives routine is still in use as a way to increase data durability.

The rotating drives strategy is commonly used in the following scenarios:

• Offsite highly durable physical data storage
• Maintenance and recovery of big data volumes that must be restored quickly and reliably, so numerous backup copies on different media are stored separately offline
• In controlled-access enterprises, where data can be stored only on authorized devices
• For long-term data storage with low access delay (e.g. monthly customer requests archive).

There are many tactics for the rotating drives approach, as well as media suitable for it.

How It Works

Backup plans save data incrementally: the initial seed is performed during the first backup plan run, then the backup is updated with new files or modified files. Managed Backup automatically recognizes drives that are used for rotation within the backup plan, but only modified data is uploaded by default. Usually, this reduces time and network expenses for classic backup, but it doesn’t suit the rotation strategy.

To solve this issue, Managed Backup is equipped with a synchronization feature that analyzes the attached storage and reports the difference between its actual and expected contents. Thus, the attached drive and repository metadata are synchronized, and the next backup plan is also configured to upload all data needed to create a full copy on a rotating device.

Configure Rotate Drives Plan in the Management Console

To Create Rotating Drives Plan

1. Open the Management Console.
2. Navigate to Computers or Backup > Computers (if you use the classic user experience, use Computers > Remote Management).
3. In the list of computers, find the one you want to create a rotating drives backup plan for, then click the Configure icon in the Backup column.

4. In the side panel, click +, then select Files backup plan (legacy).
5. Specify settings for the backup plan.

6. Expand the Backup Storage section.

7. Specify the rotating device. In case the storage account for rotating drives does not exist, create it in the Storage Accounts menu. To learn how to do it, refer to the Storage Accounts chapter.

8. Once you are finished with the rotating drives backup plan settings, click Save.

9. Use CLI to edit the backup plan and enable repository synchronization before the backup plan run. You can also use the PowerShell module for this purpose.

10. Change <SyncBeforeRun>false</SyncBeforeRun> to <SyncBeforeRun>true</SyncBeforeRun>

cbb editBackupPlan -id "Backup plan ID" -sync

11. Run the rotating drives backup plan. To do this, in the side panel where you create the backup plan, select the rotating drives backup plan, then click the Play button.