The VSP One Block 85 storage system supports parity groups (6D+2P and 14D+2P) as well as traditional RAID parity groups (6D+2P, 14D+2P, 3D+1P, 7D+1P, 2D+2D). These RAID levels can be intermixed among RAID groups in the storage system. Different capacity SSDs cannot be intermixed in one RAID group. Device emulation types cannot be intermixed in one RAID group.
For RAID 5 (7D+1P), RAID 6 (6D+2P), and RAID 6 (14D+2P), a maximum of 2,048 LDEVs (CVs) (see Virtual LVI specifications for mainframe systems) and a certain amount of free space are available in one RAID group.
The following table shows the number of CUs and LDEVs in the storage system.
| Storage system | CU | LDEV | ||
|---|---|---|---|---|
| Number | Range | Number | Range | |
| VSP One Block 85 | 255 | 0x00 to 0xFE | 65,280 | 0 to 65,279 |
The Create LDEV and Delete LDEV functions are performed on each RAID group. RAID groups are also separated from each other by boundary limitations. Therefore, you cannot define a volume across two or more RAID groups beyond these boundaries.
As the result of creating and deleting LDEVs, a RAID group contains CV, and free spaces that are delimited in logical cylinders. Sequential free spaces are combined into a single free space.