Using Snapshots in QTS

Applicable Products

QTS 4.3.4 and later

Introduction

Snapshots provide a block-level protection and local backup solution for your data. A snapshot records the state of your data at a specific point in time. Data can then be restored to this state in the event of accidental deletion or modification.

Snapshots stored outside of volumes and LUNs, in free storage pool space. This means they are not affected by file system changes and also makes it easier for users to control the number of snapshots stored on the NAS.

Requirements

• Snapshots are supported on most QNAP NAS with an Intel or AMD x86 CPU, running QTS 4.2 or later.
• From QTS 4.3.4, snapshots are supported on the following ARM-based NAS models: TS-1635, TS-831X, TS-531X, TS-431X. Support for other ARM models will be added in the future.
• The NAS must have least 1 GB of installed memory (previously the memory requirement was 4GB)
• The following series/models do not support snapshots: HS-x10, TAS-x68, TS-x69/U, TS-x59/U, TS-x39/U, TS-x31/U, TS-x28, TS-x21, TS-x20, TS-x19/U, TS-x12, TS-x10/U, TS-x09/U, TS-x01, TS-x00.

The maximum number of snapshots your NAS can store depends on the NAS model and how much memory is installed. For more details and the latest list of supported models, see: https://www.qnap.com/solution/snapshots.

Using Snapshots in QTS 4.3.4

Ensure that:

• Your NAS has been updated to QTS 4.3.4 or later.
• You have at least one storage pool, and one volume or LUN.

1. Go to Storage & Snapshots > Snapshot.
2. Select a volume or LUN.
3. Click Take Snapshot then click OK.
   QTS creates a snapshot.
   
4. Click on the volume or LUN’s name to open Snapshot Manager.
   Snapshot Manager enables you to view or delete snapshots, and restore data.
5. Select a snapshot to restore data.
   To restore individual files, select one or more files and folders then click Restore. 
   To restore all data on the volume or LUN, click Revert Volume Snapshot.
   
6. Click Snapshots Settings to configure a snapshot schedule.
   QTS can take snapshots at regular intervals (hourly, daily, weekly, monthly) to ensure your data is always protected.
7. Click Guaranteed Snapshot Space > Configure to reserve space on your NAS for snapshots.
   Guaranteed Snapshot Space ensures that new snapshots can always be taken. All volumes and LUNs can use this space.
   
8. Optional: Manage Previous Versions in Windows.
   Windows users can view and restore files from snapshots using the Previous Versions feature in Windows.
   To enable this feature, go to Storage & Snapshots > Global Settings > Snapshots, and then click Enable Windows Previous Versions.
   Note

   To keep the snapshot ACL in Previous Versions on Windows, enable advanced folder permissions in Control Panel > Privilege > Shared Folders > Advanced Permissions, and configure the subfolder permissions before taking the snapshot.

Why am I Unable To Use Snapshots in QTS 4.3.4?

The NAS must have 1GB or more of memory

Snapshots use a lot of memory. To ensure system stability, all snapshot features are disabled on NAS with less than 1GB of memory installed.

There is also a limit on the maximum number of snapshots per volume/LUN and per NAS, which depends on the NAS model and the amount of installed memory.
You can add more memory to your NAS to remove these limitations.

Snapshots cannot protect legacy volumes and static volumes

Snapshots are not stored on volumes or LUNs, instead they use free storage pool. Only thick volumes, thin volumes and block-based LUNs created in a storage pool support snapshots.
File-based LUNs can be protected by taking a snapshot of its parent volume.

Your storage pool must support snapshots

When a NAS running an earlier version of QTS with no snapshot support is updated to QTS 4.3.4, existing storage pools will be unable to use snapshots. Only new storage pools created after the QTS 4.3.4 update support snapshots.

To work around this issue, back up all data in the old storage pool to an external storage device, another NAS or to the cloud using Hybrid Backup Sync.

Hybrid Backup Sync can be downloaded from the App Center. For details, see https://www.qnap.com/solution/hybrid-backup-sync.

LUNs can also be backed up using LUN Backup in Storage & Snapshots. Using this feature you can export the LUN to an image file, and then later restore it as a block-based or file-based LUN.

After verifying that the backups contain a complete copy of all of your data, use “Storage & Snapshots” to delete the old legacy storage pool and create a new storage pool.

Alternatively if your NAS has any free drive bays, or if you have an expansion unit, you can add more drives to the NAS. Using these free drives, create a new storage pool and then move all data from the old pool to the new one.