26.6. Creating a Snapshot of Hadoop enabled Red Hat Gluster Storage Volumes

You have an existing Red Hat Gluster Storage volume and you created a snapshot of that volume but you are not yet using the volume with Hadoop. You then add more data to the volume and decide later that you want to rollback the volume's contents. You rollback the contents by restoring the snapshot. The volume can then be enabled later to support Hadoop workloads the same way that a newly created volume does.

You are running Hadoop workloads on the volume prior to the snapshot being created. You then create a snapshot of the volume and later restore from the snapshot. Hadoop continues to work on the volume once it is restored.

In this scenario, instead of restoring the full volume, only a subset of the files are restored that may have been lost or corrupted. This means that certain files that existed when the volume was originally snapped have subsequently been deleted. You want to restore just those files back from the Snapshot and add them to the current volume state. This means that the files will be copied from the snapshot into the volume. Once the copy has occurred, Hadoop workloads will run on the volume as normal.