Copying hydrated data to tape storage for disaster recovery

You can copy data from a primary container storage pool to a copy storage pool on tape. Tape can be a cost-effective alternative for storing a hydrated copy of your data, which can be used for disaster recovery.

About this task

Use storage rules to automatically create a back up copy of a directory-container storage pool on disk or an on-premises cloud-container storage pool to tape storage, creating a fully hydrated, air-gapped copy for disaster recovery. During the copy operation, any data compression or deduplication on the container storage pool is reversed to create a hydrated copy of the original client data. In case of a disaster, hydrated data can be restored directly from tape volumes to clients. You can create an onsite copy, an offsite copy, or both. One tape copy can be taken to an offsite disaster recovery location. Another copy can be kept onsite to expedite recovery from less-critical failures. You are not limited to two tape copies. However, if you create three or more data copies, you would have to run three or more backup operations daily. The operations might exceed your backup window.

A hydrated backup copy on tape provides the following advantages:
Disaster recovery protection and a streamlined process for restoring data
A fully hydrated copy of your container storage pool helps to support fast recovery of your data in a disaster. If a disaster occurs, clients can be restored directly from the tape volumes. You don't have to restore your directory-container storage pool before you restore data to clients.
Air-gapped copy of your critical data
By storing a backup copy of your container storage pool on tape, you create an air-gapped copy of your data. An air-gapped tape copy is better protected against ransomware and can be used to recover your data after an onsite ransomware attack.

To schedule a copy operation for a container storage pool, you must define a copy storage rule. Copy storage rules specify the client data to copy, the duration of the operation, and the schedule of the operation. For each copy storage rule that you define, the server creates a schedule to automatically run the BACKUP STGPOOL command to create a copy of your container storage pool to tape. When you define a copy storage rule, you specify one or more container storage pools, which contain the client data to be backed up. You also specify the copy storage pool that represents the tape volumes and define the maximum number of processes that will run during the copy operation. To keep the tape backups current, configure the storage rule to run at a scheduled time of day and for a set duration. To run a copy storage rule outside of the scheduled time that is defined by the storage rule, issue the START STGRULE command. When you explicitly start a copy storage rule, the storage rule runs until all eligible data is copied to tape.

You can define copy subrules for a copy storage rule. Subrules specify exceptions to the parent rule. If for example, you don't want to back up the data for all client nodes or virtual machines in a storage pool, you can define subrules that include or exclude specific nodes or virtual machines. Storage rules provide the flexibility to use a single rule to back up multiple storage pools, and subrules provide granular control over which nodes are backed up and the backup destination for each node.

Planning considerations:
  • When data is moved out of a container storage pool, for example, during tiering operations, the data is not deleted from the tape copy. Instead, the expiration of a file in a source primary storage pool determines when the file is deleted from the target storage pool on tape.
  • Copy storage rules do not initiate reclamation processing. Reclamation settings, which are specified on administrative commands such as RECLAIM STGPOOL and DEFINE STGPOOL, determine when a tape volume becomes eligible for reclamation and reuse. To reclaim space on the tape volumes in a copy storage pool, use the administrative schedule to run the RECLAIM STGPOOL command at regular intervals.
    Tip: You can also specify reclamation thresholds when you define or update a storage pool by using the DEFINE STGPOOL or UPDATE STGPOOL commands with the RECLAIMPROCESS parameter.
  • Copy storage rules are designed to create an air-gapped copy of your data for disaster recovery, not for repairing container storage pools. You cannot use the RESTORE STGPOOL or REPAIR STGPOOL commands to repair or restore data in a container storage pool from the target storage pool on tape. If data in a source container storage pool is damaged, you can use the backup-archive client to restore data from the copy storage pool. For information, see Recovering data on backup-archive clients and container storage pools by using a hydrated tape copy.
  • The target storage pool that you specify in a copy storage rule can also be used as a target storage pool for non-container storage pools that are already running the BACKUP STGPOOL command. The target copy storage pool does not have to be used only for copy storage rule data.
  • In a replication environment, you can define storage rules to copy data from either a source replication server, a target replication server, or both.
  • When you define a copy storage rule, collocation settings that are specified for the target copy storage pool are preserved and apply to the rehydrated data from the container storage pool.


To define a storage rule for copying a container storage pool to tape, follow the instructions in Defining a copy storage rule.