The following figure shows a logical view of the 3-node setup:
Figure 6. Logical architecture
In the two-layer PowerFlex system, the SDC is installed on the compute-only host, while the MDM and SDS components are installed on back-end, storage-only nodes. The SDS aggregates and serves raw local storage in each node and shares that storage as part of the PowerFlex cluster. A single Storage Pool is created using all the disks on each node within the Protection Domains, volumes are then provisioned from the Storage Pool and presented to the compute hosts, which Oracle Linux Virtualization Manager will utilize as storage domains. From the storage domain, respective size disks are carved out to meet the Oracle RAC ASM disk group database requirements, including volumes for data, redo logging, voting disk, the grid infrastructure management repository, and the flash recovery area. The volumes are mapped to the respective VMs to be used for Oracle Grid Infrastructure and Oracle Database installation.