This command gives users the ability to restore a backup to a raw image or a qcow2 image. If the backup is based on a backing file, users should provide the backing file as a qcow2 image with --backing file parameter.

1. Copy the yaml template: Make a copy of examples/restore_to_file.yaml.template as a new file, for example, restore.yaml.
2. Set the node which the output file should be placed on by replacing <NODE_NAME>, for example, node1.
3. Specify the host path of output file by modifying field hostpath of volume disk-directory. By default the directory is /tmp/restore/.
4. Set the first argument (backup url) by replacing <BACKUP_URL>, for example, s3://<your-bucket-name>@<your-aws-region>/backupstore?backup=<backup-name>&volume=<volume-name>.
   • <backup-name> and <volume-name> can be retrieved from backup.cfg stored in the backup destination folder, for example, backup_backup-72bcbdad913546cf.cfg. The content will be like below:

     {"Name":"backup-72bcbdad913546cf","VolumeName":"volume_1","SnapshotName":"79758033-a670-4724-906f-41921f53c475"}
     

5. Set argument output-file by replacing <OUTPUT_FILE>, for example, volume.raw or volume.qcow2.
6. Set argument output-format by replacing <OUTPUT_FORMAT>. The supported options are raw or qcow2.
7. Set argument longhorn-version by replacing <LONGHORN_VERSION>, for example, v1.14.0
8. Set the S3 Credential Secret by replacing <S3_SECRET_NAME>, for example, rustfs-secret.
   • The credential secret can be referenced here and must be created in the longhorn-system namespace.
9. Execute the yaml using command:

   kubectl create -f restore.yaml
   

10. Watch the result using:

    kubectl -n longhorn-system get pod restore-to-file -w
    

After the pod status changed to Completed, you should able to find <OUTPUT_FILE> at /tmp/restore on the <NODE_NAME>.

We also provide a script, restore-backup-to-file.sh, to restore a backup. The following parameters should be specified:

• --backup-url: Specifies the backups S3/NFS URL. For example, s3://backupbucket@us-east-1/backupstore?backup=backup-bd326da2c4414b02&volume=volumeexamplename"
• --output-file: Set the output file name. For example, volume.raw
• --output-format: Set the output file format. For example, raw or qcow2
• --version: Specifies the version of Longhorn to use. For example, v1.14.0

Optional parameters can be specified:

• --aws-access-key: Specifies the AWS credentials access key if backup is s3.
• --aws-secret-access-key: Specifies the AWS credentials access secret key if backup is s3.
• --backing-file: Specifies the backing image. For example, /tmp/backingfile.qcow2

The output image files can be found in the /tmp/restore folder after the script has finished running.