RAID Level Concept

A description of each RAID level is shown below.

• RAID0 (Striping)

  Data is divided into blocks and allocated across multiple drives.

• RAID1 (Mirroring)

  The data is stored on two duplicated drives at the same time.

  If one drive fails, the other drive continues operation.

• RAID1+0 (Striping of Pairs of Mirrored Drives)

  RAID1+0 combines the high I/O performance of RAID0 (striping) with the reliability of RAID1 (mirroring).

• RAID5 (Striping with Distributed Parity)

  Data is divided into blocks and allocated across multiple drives together with parity information created from the data in order to ensure the redundancy of the data.

• RAID5+0 (Double Striping with Distributed Parity)

  Multiple RAID5 volumes are RAID0 striped. For large capacity configurations, RAID5+0 provides better performance, better reliability, and shorter rebuilding times than RAID5.

• RAID6 (Striping with Double Distributed Parity)

  Allocating two different parities on different drives (double parity) makes it possible to recover from up to two drive failures.

• RAID6-FR (Striping with Double Distributed Parity which Provides High-Speed Rebuild Capabilities)

  Distributing multiple data groups and reserved space equivalent to hot spares to the configuration drives makes it possible to recover from up to two drive failures. RAID6-FR requires less build time than RAID6.