The PowerFlex system organizes the storage cluster into protection domains and storage pools.
A protection domain is a subset of storage data servers (SDS), the functionality of the PowerFlex SVM that runs on each host. At least four hosts are required in a protection domain. All the hosts in the domain must have the same configuration—for example, one protection domain for the four-socket R840 nodes and another protection domain for the two-socket R640 nodes.
A storage pool is a subset of the physical storage devices in a protection domain. The persistent devices (data and log) of the SAP HANA production nodes require the capacity to be allocated on SSD storage pools. Each PowerFlex node requires at least eight SSDs. The size and number of SSDs depend on the capacity requirements, as described in Capacity requirements.