RAID LEVEL 0_1: High Data Transfer Performance

 

RAID Level 0+1 requires a minimum of 4 drives to implement

Characteristics & Advantages

  • RAID 0+1 is implemented as a mirrored array whose segments are RAID 0 arrays
  • RAID 0+1 has the same fault tolerance as RAID level 5
  • RAID 0+1 has the same overhead for fault-tolerance as mirroring alone
  • High I/O rates are achieved thanks to multiple stripe segments
  • Excellent solution for sites that need high performance but are not concerned with achieving maximum reliability

Disadvantages

  • RAID 0+1 is NOT to be confused with RAID 10. A single drive failure will cause the whole array to become, in essence, a RAID Level 0 array
  • Very expensive / High overhead
  • All drives must move in parallel to proper track lowering sustained performance
  • Very limited scalability at a very high inherent cost

Recommended Applications

  • Imaging applications
  • General fileserver

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