Defining a tiering rule

You can define a storage rule to implement tiering, which moves data from a directory-container storage pool on disk to cloud or tape storage. When the storage rule is active, eligible data is tiered daily.

Before you begin

Consider whether tiering is appropriate, given your storage environment and business goals. For instructions, see Determining whether tiering is appropriate for your storage environment.
Review the following restrictions:
- A tiering rule defines when data is tiered from one or more directory-container storage pools to a cloud-container or tape storage pool. The source and target storage pools must exist before you create the tiering rule.
- For cloud tiering, the target must be a cloud-container storage pool on a Microsoft Azure cloud computing system or on a cloud computing system that uses the Simple Storage Service (S3) protocol, such as IBM Cloud® Object Storage or Amazon Web Services (AWS) S3. For the latest information about cloud object storage services that are supported, see technote 2000915.
- For tape tiering, the target storage pool must be defined for a physical or virtual tape library.
- If you use copy storage rules and tiering rules to copy and tier data from the same node, filespace, and source container storage pool, data is tiered after copy operations are completed. When a tiering rule runs, the server skips any files that are not copied, and data is tiered the next time that the tiering rule runs. If more than one copy storage rule is defined to copy data for a node and filespace, all copy operations must be completed before the tiering operation begins.
  Tip: To help maintain the currency of data in the target storage pool, you can run the BACKUP STGPOOL command as described in step 6.
  For information about using copy and tiering rules for data on the same node, filespace, and source container storage pool, see Managing copy and tiering storage rules.
To optimize tiering, consider using this strategy:
1. Create a tiering rule. By default, the newly created rule is inactive.
2. Create a subrule to tier data from a single client. To select the best option for tiering data from the client, see Determining whether tiering is appropriate for your storage environment.
3. Modify the parent tiering rule to make it active. The parent rule and its subrule will run daily.
4. Verify the tiering results. If necessary, update the subrule to add more clients or create additional subrules.
Tip: To view an example of how to set up tiering, see Tiering scenario: A step-by-step example.
Before you tier data to cloud storage, configure replication to create a backup copy of the data in the directory-container storage pool. The preferred method is to configure replication with the PROTECT STGPOOL command. For instructions, see Replicating client data to another server.
Restriction: Data that is tiered to cloud storage is no longer protected by the PROTECT STGPOOL process.
Before you tier data to tape storage, consider whether to enable collocation. Collocation can reduce the number of volumes that must be accessed when a large amount of data must be restored. You can enable collocation by specifying the COLLOCATE parameter on the DEFINE STGPOOL or UPDATE STGPOOL command.
If you plan to apply a tiering rule and a copy storage rule to the same node, filespace, and source container storage pool, consider scheduling regular backup operations to maintain the currency of data in the target storage pool.
To schedule regular backup operations for a directory-container storage pool, use the BACKUP STGPOOL command. Specify the same target storage pool that is defined in the copy storage rule.

Procedure

To define a tiering rule, complete the following steps:

On the Operations Center menu bar, click Storage > Storage Rules.
On the Storage Rules page, click +Create Rule.

Tip: To help ensure that active data can be quickly restored, select the option to tier only inactive data. By selecting this option, you ensure that active data remains on local disk storage, from which restore operations are typically faster.
On the Create Rule page, complete the fields and click Create.

Tip: Alternatively, you can define a storage rule by using the DEFINE STGRULE command. For more information, see DEFINE STGRULE (Define a storage rule for tiering).

Results

The storage rule is defined. By default, the storage rule is inactive. If you activate the storage rule, the rule runs on a daily schedule.

Tiering results differ, depending on whether the data is tiered to cloud or tape storage:

Cloud storage: If data in a directory-container storage pool is compressed, encrypted, or both, the data is moved to the cloud-container storage pool in the same format. All extents that are required to rebuild a cloud object are copied to the tier, if the extents are not already there.
Tape storage: If data in a directory-container storage pool is compressed or deduplicated, and the data is tiered to tape, the data is no longer compressed or deduplicated. If data is encrypted on a client and tiered to tape, the data remains encrypted on tape. If data is encrypted by the IBM Spectrum® Protect server and tiered to tape, the data is decrypted on tape.

What to do next

Optionally, you can take the following actions:

To specify exceptions to the storage rule, define one or more subrules. For instructions about defining subrules, see Defining a tiering subrule.
When you are ready to activate the tiering rule, on the Properties tab, click Modify, click the Active toggle, and click Save. The active tiering rule and any subrules run daily at the scheduled time. (Alternatively, activate the storage rule by issuing the UPDATE STGRULE command with the ACTIVE=YES setting.)
To protect data that was tiered to tape, encrypt tape drives by following the instructions in Configuring tape drive encryption.
To ensure that data that was tiered to tape is backed up, set up a schedule to run the BACKUP STGPOOL command daily. For more information, see DEFINE SCHEDULE (Define a schedule for an administrative command).