Virtual volume RAID

Unlike traditional RAID, all HPE 3PAR RAID levels distribute data across all available physical drives using one of the following methods:

  • Data striping, which improves speed by performing I/O with an entire group of physical drives at the same time.

  • Data mirroring, which provides data redundancy by storing data and a copy of the data.

  • Parity error checking, which provides automatic detection and correction if there is corruption of a physical drive.

HPE 3PAR storage systems support the following RAID types for virtual volumes. Each RAID type uses a different combination of RAID methods that impact data redundancy, the amount of physical drive space used, and I/O speed. Hewlett Packard Enterprise recommends that you not use RAID 0. Use RAID 1, RAID 5, or RAID 6 instead to include data protection (fault tolerance).

Tip: When creating common provisioning groups with HPE SSMC, the default choice for RAID type is RAID 6 with FC and NL device types, and RAID 5 for SSD device types.

RAID 0 – Data is striped across chunklets on different physical drives that might be in different drive magazines or drive enclosures. RAID 0 improves performance but does not provide data protection (fault tolerance).

RAID 1 – Data is striped across RAID 1 sets. A RAID 1 set includes chunklets that contain the same data. The chunklets are distributed across different physical drives that might be located in different drive magazines or drive enclosures. RAID 1 sets are also known as a mirror sets. A RAID 1 set can function with the loss of all but one of the chunklets in the set.

RAID 5 – Data is striped across RAID 5 sets. A RAID 5 set includes chunklets for data and chunklets for parity. The chunklets are distributed across different physical drives that might be located in different drive magazines or drive enclosures. RAID 5 sets are also known as parity sets. A RAID 5 set can function with the loss of any one of the chunklets in the set.

RAID 6 – Data is striped across RAID MP sets. A RAID MP set includes one chunklet for data and two chunklets for parity. The chunklets in each RAID MP set are distributed across different physical drives that might be located in different drive magazines or drive enclosures. RAID MP is also known as RAID 6 or a double-parity set. A RAID MP set can function with the loss of any two of the chunklets in the set.
NOTE:

For an array with the OS 4.2.0, RAID 6 is the only supported RAID Type. The Set size is automatically assigned.

Learn more: Virtual volumes overview.