Snapshots
Snapshots enable the saving of a filesystem state to a directory and can be used for backup, archiving and testing purposes.
About snapshots
Snapshots allow the saving of a filesystem state to a .snapshots directory located under the root filesystem. They can be used for:
- Physical backup: The snapshot directory can be copied into a different storage system, possibly on another site, using either the Content Software for File system Snap-To-Object feature or a third-party software.
- Logical backup: Periodic snapshots enable filesystem restoration to a previous state if logical data corruption occurs.
- Archive: Periodic snapshots enable the accessing of a previous filesystem state for compliance or other needs.
- DevOps environments: Writable snapshots enable the execution of software tests on copies of the data.
Snapshots have no impact on system performance and can be taken for each filesystem while applications are running. They consume minimal space, according to the actual differences between the filesystem and the snapshots, or between the snapshots, in 4K granularity.
By default, snapshots are read-only, and any attempt to change the content of a read-only snapshot returns an error message.
It is possible to create a writable snapshot or update an existing snapshot to be writable. However, a writable snapshot cannot be changed to a read-only snapshot.
The Content Software for File system supports the following snapshot operations:
- View snapshots.
- Create a snapshot of an existing filesystem.
- Delete a snapshot.
- Access a snapshot under a dedicated directory name.
- Restore a filesystem from a snapshot.
- Make snapshots writable.
- Create a snapshot of a snapshot (relevant for writable snapshots, or for read-only snapshots before being made writable).
- List of snapshots and obtaining their metadata.
- Schedule automaticsnapshots. See Snapshot management.
Managing snapshots using the GUI
How to manage snapshots using the GUI.
Viewing snapshots using the GUI
To view the snapshot of filesystem
Procedure
To display all snapshots, select Manage > Snapshots from the menu. The Snapshots page opens.
To display a snapshot of a selected filesystem, do one of the following:
- Select the Filesystem filter. Then, select the filesystem from the list.
- From the menu, select Manage > Filesystems. From the filesystem, select the three dots, and from the menu, select Go To Snapshot.
Creating a snapshot using the GUI
Before you begin
You can create a snapshot from the Snapshots page or directly from the Filesystems page.
Create a directory for filesystem-level snapshots that serves as the access point for snapshots.
Procedure to create a snapshot.
Procedure
Do one of the following:
- From the menu, select Manage > Snapshots. From the Snapshots page, select +Create. The Create Snapshot dialog opens.
- From the menu, select Manage > Filesystems. From the Filesystems page, select the three dots, and from the menu, select Create Snapshot. (The source filesystem is automatically set.)
On the Create Snapshot dialog set the following properties:
- Name: A unique name for the filesystem snapshot.
- Access Point: A name of the newly-created directory for filesystem-level snapshots that serves as the snapshot's access point.
- Writable: Determines whether to set the snapshot to be writable.
- Source Filesystem: The source filesystem from which to create the snapshot.
- Upload to local object store: Determines whether to upload the snapshot to a local object store. You can also upload the snapshot later (see Snap-To-Object).
- Upload to remote object store: Determines whether to upload the snapshot to a remote object store. You can also upload the snapshot later.
Select Create.
Duplicate a snapshot
You can duplicate a snapshot (clone), which enables creating a writable snapshot from a read-only snapshot.
Procedure
From the menu, select Manage > Snapshots.
From the Snapshots page, select the three dots of the snapshot you want to duplicate, and from the menu, select Duplicate Snapshot.
In the Duplicate Snapshot dialog, set the properties the same way you create a snapshot. The source filesystem and source snapshot are already set.
Select Duplicate.
Deleting a snapshot using the GUI
Before you begin
When deleting a snapshot, consider the following guidelines:
- Deleting a snapshot in parallel to a snapshot upload to the same filesystem is not possible. Uploading a snapshot to a remote object store can take time. Therefore, it is advisable to delete the desired snapshot before uploading it to the remote object store.
- When uploading snapshots to both local and remote object stores. While the local and remote uploads can progress in parallel, consider the case of a remote upload in progress, then a snapshot is deleted, and later a snapshot is uploaded to the local object store. In this scenario, the local snapshot upload waits for the pending deletion of the snapshot (which happens only once the remote snapshot upload is done).
Procedure to delete a snapshot.
Procedure
From the menu, select Manage > Snapshots.
From the Snapshots page, select the three dots of the snapshot you want to delete, and from the menu, select Remove.
In the Deletion Of Snapshot message, select Yes to delete the snapshot.
Restore a snapshot to a filesystem or another snapshot
Before you begin
Restoring a snapshot to a filesystem or another snapshot (target) modifies the data and metadata of the target.
If you restore the snapshot to a filesystem, make sure to stop the IO services of the filesystem during the restore operation.
Procedure to restore a snapshot.
Procedure
From the menu, select Manage > Snapshots.
From the Snapshots page, select the three dots of the snapshot you want to restore, and from the menu, select Restore To.
In the Restore To dialog, select the destination: Filesystem or Snapshot.
Select Save.
Updating a snapshot using the GUI
You can update the snapshot name and access point properties.
Procedure
From the menu, select Manage > Snapshots.
From the Snapshots page, select the three dots of the snapshot you want to update, and from the menu, select Edit.
Modify the Name and Access Point properties as required.
Select Save.
