Disk Pools, Volumes, and Mapping¶

Disk pools should be created and sized based on the number of object storage nodes connecting to the storage subsystem. A minimum of 11 drives per drive pool is required, but the recommended number of drives in a drive pool is equal to N, where N is the total number of drives in the storage subsystem divided by the total number of attached object storage nodes.

Assuming no SSD drives are present, create 3 volumes of equal capacity on each drive pool. Be sure to select the “Map Later” option to ensure the mapping to a host takes place after all volumes are created. If SSDs are present, be sure to create separate disk pools that only contain SSDs. Swift documentation recommends that SSDs be leveraged for account and container type objects.

The default mapping for volumes to hosts (via LUN mapping) is to expose all volumes to all hosts. To ensure multiple hosts are not accessing the same LUN concurrently, it is recommended that each volume be explicitly mapped to the WWN for the appropriate host it should connect to. If the default mapping is utilized, extreme care must be exercised to ensure the correct mapping is retained to prevent data corruption.