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Storage types

Storage types

The Storage Scale solution offers three different storage types: scratch, persistent, and evaluation.

Scratch storage

A scratch configuration uses virtual server instances with instance storage. If a virtual server instance with instance storage is powered off then all the data that is stored on the instance storage volumes is rendered inaccessible after a subsequent power up of the virtual server instance. Therefore, use of scratch storage is not recommended for long-running or mission-critical workloads.

Persistent storage

A persistent configuration uses bare metal servers with locally attached NVMe storage. In addition to higher resilience, persistent storage provides higher performance and capacity than scratch storage.

Evaluation storage

Evaluation storage is based on Storage Scale Developer Edition. This option supports all advanced features of Storage Scale Data Management Edition but is limited to 12 TB of storage.

With evaluation storage, you can try out the Storage Scale solution on IBM Cloud® without a license. The automated deployment is done on virtual server instances with instance storage, with Storage Scale Developer Edition packages, and is available only for prototyping and testing purposes.

Storage type comparison

Storage Scale storage types comparison
The first row of the table describes a Storage Scale feature, and the first column describes the specifics of that feature as it pertains to scratch storage. The second column describes the specifics of persistent storage, and the third column describes the specifics of evaluation storage, which map to the Storage Scale feature in each row.
Scratch (default) Persistent Evaluation
Storage cluster nodes Virtual server instances Bare metal servers Virtual server instances
Storage cluster node count Min 2
Max 64
Min 2
Max 32
Min 2
Max 64
Compute cluster node count Min 3
Max 64
Min 3
Max 64
Min 3
Max 64
Protocol node count Min 2
Max 32
Min 2
Max 32
Min 2
Max 32
Client node count Min 2
Max 2000
Min 2
Max 2000
Min 2
Max 2000
AFM node count Min 1
Max 16
Min 1
Max 16
Min 1
Max 16
Storage cluster OS support RHEL 8.10
(custom or stock images)
RHEL 8.10
(custom or stock images)
RHEL 8.10
(custom image)
Compute cluster OS support RHEL 8.10
(custom or stock images)
RHEL 8.10
(custom or stock images)
RHEL 8.10
(custom image)
Protocol nodes RHEL 8.10
(custom image)
RHEL 8.10
(custom image)
RHEL 8.10
(custom image)
Client nodes RHEL 7.9, 8.8, 8.10, 9.2
Cent 7.9(stock image)
RHEL 7.9, 8.8, 8.10, 9.2
Cent 7.9(stock image)
RHEL 7.9, 8.8, 8.10, 9.2
Cent 7.9(stock image)
Storage Scale edition and version Storage Scale Data Management Edition v5.2.1.1 Storage Scale Data Management Edition v5.2.1.1 Storage Scale Developer Edition v5.2.1.0
IBM Customer Number required? Yes Yes No
Customer support available? Yes Yes No

For more information about Storage Scale editions, see IBM Storage Scale product editions.