Cloning cluster data from a defined other location 

Clone cluster data from one DSE cluster to another using the Restore Backup feature in OpsCenter. This workflow does not require the source and target clusters to both be managed by the same OpsCenter instance. This workflow does not necessarily even require another existing cluster instance. The data can be cloned providing it was backed up to an available Local FS or an Amazon S3 location.

Clone cluster data from one DSE cluster to another using the Restore Backup feature in OpsCenter. This workflow does not require the source and target clusters to both be managed by the same OpsCenter instance. This workflow does not necessarily even require another existing cluster instance. The data can be cloned providing it was backed up to an available Local FS or an Amazon S3 location.

This procedure steps you through the basic required selections in each of the three restore dialogs presented during the workflow.

Prerequisites

To clone the cluster data, there must be an existing backup of the cluster to a Local FS or an Amazon S3 location. See adding a backup location.
Note: Cloning encrypted tables to a different cluster does not work unless the encryption keys are identical, which is typically not the case.
Important: The Backup Service requires control over the data and structure of its destination locations. The AWS S3 bucket and the Local file system destinations must be dedicated for use only by OpsCenter. Any additional directories or files in those destinations can prevent the Backup Service from properly conducting a Backup or Restore operation.

Procedure

  1. Click the target cluster name > Services.
  2. Click the Details link for the Backup Service.
  3. In the Activity tab, click Restore Backup.
  4. Click the Other Location tab.
    The Step 1 of 3: Select Backup Restore from Backup dialog appears.

  5. Required: Select the Location. Available options are:
    • Amazon S3 (default): Go to 6.
    • Local FS: Go to 7.
  6. If the location is Amazon S3:
    1. Required: Enter the S3 Bucket name.
    2. Required: Enter your AWS credentials in AWS Key and AWS Secret.
  7. Required: If the location is Local FS, enter the Path to the backups.
  8. Click Next.
    The Step 2 of 3: Select Backup Version dialog appears populated with the available backups at the selected location.

    Step 2 of 3 restore backup dialog other location tab

  9. Required: Select the backup to restore and click Next.
    The Step 3 of 3: Configure and Restore dialog appears.

    Step 3 of 3 restore backup dialog other location tab

  10. Required: Select the keyspaces or tables from the available Keyspaces.

    To select only specific tables, expand the keyspace name and select the tables.

    Note: Keep the following caveats in mind when creating and restoring backups:
    • Restoring a snapshot that contains only the system keyspace is not allowed. There must be both system and non-system keyspaces, or only non-system keyspaces in the snapshot you want to restore.
    • Restoring a snapshot that does not contain a table definition is not allowed.
    • Restoring a snapshot to a location with insufficient disk space fails. The Restore Report indicates which nodes do not have sufficient space and how much space is necessary for a successful restore. For more information and tips for preventative measures, see Monitoring sufficient disk space for restoring backups.
  11. Required: In the Location list, select the cluster to clone the data to.
  12. Required: Click Restore Backup.
    The Confirm Restore dialog appears.
    Confirm restore operation dialog
    Warning: If a value was not set for throttling stream output, a warning message indicates the consequences of unthrottled restores. The throttle warning only appears for versions of DSE from 4.8.7 and later. Either click Cancel and set the throttle value in the Restore from Backup dialog, set the values in cassandra.yaml (stream_throughput_outbound_megabits_per_sec and inter_dc_stream_throughput_outbound_megabits_per_sec), or proceed anyway at risk of network bottlenecks.
    Tip: If you are using LCM to manage DSE cluster configuration, update Cluster Communication settings in cassandra.yaml in the config profile for the cluster and run a configuration job. Stream throughput (not inter-dc) is already set to 200 in LCM defaults.

    Update throttle options in LCM

  13. Review the information to determine what adjustments if any need to be made to the current schema:
    • To rectify the schema issues and try the restore again afterward, click Cancel.
    • To proceed despite the schema mismatch, click Continue Restore.
      Warning: Attempting to restore a backup with an incompatible schema might result in corrupt or inaccessible data. Before forcing the restore, you might want to back up your current data.

Results

The progress and details of the restore operation are displayed in the Restore Report.