Level Techniques Description Min. Drives Failure Conditions Pros/Cons Uses
RAID O Disk striping (no fault tolerance) Data is broken into stripes which 2 When one drive fails, the entire array is compromised. Offers Best performance Video editing and production
are sent to each disk in the array.
No fault tolerance.
RAID 1 Disk mirroring Data on one drive is mirrored on another. 2 If one drive fails, data is not lost. If both drives fail, the data is lost. 100% redundancy of data/Slower performance and 50% loss of storage space. Accounting, payroll, financial
RAID 2 Byte level striping with Hamming code ECC Data is split at the bit level over a number of data and ECC disks. Up to 14+ Only one drive may fail and still be recoverable "on the fly". On the fly data error correction/Extremely high cost. No commercial uses
RAID 3 Byte level striping with dedicated parity Data is striped at the byte-level, across multiple disks. 3 When more then one drive fails, the array is compromised. High read/write data transfer rates/Complex controller design Image and video editing
RAID 4 Block level striping with dedicated parity Data is striped in blocks across data disk, with parity store on a separate disk. 3 When more then one drive fails, the array is compromised. High Read/Low Write data transaction rates. General purpose
RAID 5 Block level striping with distributed parity Data and parity are striped in blocks across all disks. 3 When more then one drive fails, the array is compromised. High Read data transaction rates/ Complex controller design Web, database or file servers
http://www.raidrecoveryguide.com/levels2.html
RAID O Disk striping (no fault tolerance) Data is broken into stripes which 2 When one drive fails, the entire array is compromised. Offers Best performance Video editing and production
are sent to each disk in the array.
No fault tolerance.
RAID 1 Disk mirroring Data on one drive is mirrored on another. 2 If one drive fails, data is not lost. If both drives fail, the data is lost. 100% redundancy of data/Slower performance and 50% loss of storage space. Accounting, payroll, financial
RAID 2 Byte level striping with Hamming code ECC Data is split at the bit level over a number of data and ECC disks. Up to 14+ Only one drive may fail and still be recoverable "on the fly". On the fly data error correction/Extremely high cost. No commercial uses
RAID 3 Byte level striping with dedicated parity Data is striped at the byte-level, across multiple disks. 3 When more then one drive fails, the array is compromised. High read/write data transfer rates/Complex controller design Image and video editing
RAID 4 Block level striping with dedicated parity Data is striped in blocks across data disk, with parity store on a separate disk. 3 When more then one drive fails, the array is compromised. High Read/Low Write data transaction rates. General purpose
RAID 5 Block level striping with distributed parity Data and parity are striped in blocks across all disks. 3 When more then one drive fails, the array is compromised. High Read data transaction rates/ Complex controller design Web, database or file servers
http://www.raidrecoveryguide.com/levels2.html
No comments:
Post a Comment