Manage Snap-To-Object using the CLI

The Snap-To-Object feature enables the committing of all the data of a specific snapshot to an object store.

Using the CLI, you can:

• Upload a snapshot

• Create a filesystem from an uploaded snapshot

• Manage synchronous snapshots

• Recover from a remote snapshot

Upload a snapshot

Command: weka fs snapshot upload

Use the following command line to upload an existing snapshot:

weka fs snapshot upload <file-system> <snapshot> [--site site]

Parameters

Name	Value	Default
file-system*	Name of the filesystem
snapshot*	Name of the snapshot of the <file-system> filesystem to upload.
site*	Location for the snapshot upload. Mandatory only if both local and remote buckets are attached. Possible values: local or remote	Auto-selected if only one bucket for upload is attached.

Create a filesystem from an uploaded snapshot

Command: weka fs download

Use the following command line to create (or recreate) a filesystem from an existing snapshot:

weka fs download <name> <group-name> <total-capacity> <ssd-capacity> <obs-bucket> <locator> [--additional-obs additional-obs] [--snapshot-name snapshot-name] [--access-point access-point]

When creating a filesystem from a snapshot, a background cluster task automatically prefetches its metadata, providing better latency for metadata queries.

Parameters

Name	Value	Default
name*	Name of the filesystem to create.
group-name*	Name of the filesystem group in which the new filesystem is placed.
total-capacity*	The total capacity of the downloaded filesystem.
ssd-capacity*	SSD capacity of the downloaded filesystem.
obs-bucket*	Object store name for tiering.
locator*	Object store locator obtained from a previously successful snapshot upload.
additional-obs	An additional object-store name. If the data to recover reside in two object stores (a second object store attached to the filesystem, and the filesystem has not undergone full migration), this object store is attached in a read-only mode. The snapshot locator must be in the primary object store specified in the obs parameter.
snapshot-name	The downloaded snapshot name.	The uploaded snapshot name.
access-point	The downloaded snapshot access point.	The uploaded access point.

The locator can be a previously saved locator for disaster scenarios, or you can obtain the locator using the weka fs snapshot command on a system with a live filesystem with snapshots.

If you need to pause and resume the download process, use the command: weka cluster task pause / resume. To abort the download process, delete the downloaded filesystem directly. For details, see Manage background tasks.

Due to the bandwidth characteristics and potential costs when interacting with remote object stores it is not allowed to download a filesystem from a remote object-store bucket. If a snapshot on a local object-store bucket exists, it is advisable to use that one. Otherwise, follow the procedure in Recover from a remote snapshot.

For encrypted filesystem, when downloading, you must use the same KMS master key to decrypt the snapshot data. For more information, see the KMS Management section.

Manage synchronous snapshots

The workflow to manage the synchronous snapshots includes:

1. Upload snapshots using, for example, the snapshots scheduler. See Snapshot management.

2. Download the synchronous snapshot (described below).

3. Restore a specific snapshot to a filesystem. See Restore a snapshot to a filesystem or another snapshot.

Download a synchronous snapshot

Command: weka fs snapshot download

Use the following command line to download a synchronous snapshot. This command is only relevant for snapshots uploaded from a system of version 4.0 and higher:

weka fs snapshot download <file-system> <locator>

Make sure to download synchronous snapshots in chronological order. Non-chronological snapshots are inefficient and are not synchronous.

If you need to download a snapshot earlier than the latest downloaded one, for example, when you need one of the daily synchronous snapshots after the weekly synchronous snapshot was downloaded, add the --allow-non-chronological flag to download it anyway.

Parameters

Name	Value
file-system*	Name of the filesystem.
locator*	Object store locator obtained from a previously successful snapshot upload.

If you need to pause and resume the download process, use the command: weka cluster task pause / resume. To abort the download process, delete the downloaded snapshot directly. For details, see Manage background tasks.

Related topics

Synchronous snapshots

Recover from a remote snapshot

When recovering a snapshot residing on a remote object store, it is required to define the object store bucket containing the snapshot as a local bucket.

A remote object store has restrictions over the download, and we want to use a different local object store due to the QoS reasons explained in Manage object stores.

To recover a snapshot residing on a remote object store, create a new filesystem from this snapshot as follows:

1. Add a new local object-store, using weka fs tier obs add CLI command.

2. Add a local object-store bucket, referring to the bucket containing the snapshot to recover, using weka fs tier s3 add.

3. Download the filesystem, using weka fs download.

4. If the recovered filesystem should also be tiered, add a local object store bucket for tiering using weka fs tier s3 add.

5. Detach the initial object store bucket from the filesystem.

6. Assuming you want a remote backup to this filesystem, attach a remote bucket to the filesystem.

7. Remove the local object store bucket and local object store created for this procedure.