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PowerStore systems can be configured with NVMe SSDs for user data and can be expanded with additional drives to increase the amount of available storage capacity. PowerStore 1000, 3000, 5000, 7000, and 9000 series models can be expanded with SAS SSD-based expansion shelves.
Starting from PowerStoreOS 3.0, all PowerStore models can be expanded with NVMe SSD-based expansion shelves if they satisfy the Dell PowerStore hardware prerequisites. See Dell PowerStore: Introduction to the Platform. Dell Technologies recommends that all drives in a PowerStore system be the same size to maximize the usable capacity from each drive.
PowerStore DRE manages the drives in the system. All drives are automatically used to provide storage capacity. DRE groups the drives into resiliency sets to protect against drive failure. User configuration is not necessary, and dedicated hot spare drives are not required. Spare space for rebuilds is automatically distributed across all drives within each resiliency set. This configuration provides better resource utilization and enables faster rebuilding if there is a drive failure.
With the exception of the PowerStore 500 model, PowerStore systems use NVMe NVRAM drives to provide persistent storage for cached write data. PowerStore 1000 to 3200 appliances have two NVRAM drives per system, while PowerStore 5000 to 9200 appliances have four NVRAM drives per system. The extra drives mean that these systems can provide higher MBPS for large-block write workloads.
The following figure shows how the NVRAM drives are configured in the base enclosure:
Aside from the PowerStore 500T appliance model, NVMe SSD-based systems can be expanded with an expansion enclosure using up to 24 SAS SSD drives to increase the available storage capacity. The following figure shows this configuration:
For SAP HANA, Dell Technologies recommends using NVMe SSDs with a disk capacity size that allows the system capacity to fit within the base enclosure. Use ten drives at a minimum for single-drive failure tolerance, or nineteen drives for double-drive failure tolerance. The Dell SAP team tested SAP HANA performance and scalability with single parity (single tolerance R5) and dual parity (double tolerance R6) and found that the performance levels were the same for both. The SAP HANA scalability that is shown in Table 3 - FC SAN and Table 4 - NAS/NFS is therefore valid for both single-drive and double-drive failure tolerance levels.