RAID 5 is the most popular RAID technology in use today. It uses a technique that avoids the concentration of I/O on a dedicated parity disk, that occurs with RAID 4.
Although RAID 5 divides the data and creates parity information similar to RAID 4, unlike RAID 4 the parity data is written separately across multiple disks.
"Write penalty" still occurs as existing data must be pre-read before update and parity data has to be updated after the data is written.
However, RAID 5 enables multiple write orders to be implemented concurrently because updated parity data is dispersed across the multiple disks. This feature ensures higher performance compared with RAID 4.
Furthermore, some ETERNUS AF and ETERNUS DX are able to deploy disk drives where RAID6 and 5 arrays are deployed across separate drive enclosures (DE) for improved reliability. (Learn more)
Process on disk failure
RAID 5 supported:
ETERNUS AF150 S3
ETERNUS AF250 S3/S2, AF250
ETERNUS AF650 S3/S2, AF650
|Hybrid Storage Systems||
ETERNUS DX60 S5/S4/S3
ETERNUS DX100 S5/S4/S3, DX200 S5/S4/S3
ETERNUS DX500 S5/S4/S3, DX600 S5/S4/S3
ETERNUS DX900 S5
ETERNUS DX8700 S3/S2, DX8900 S4/S3
ETERNUS DX60 S2, DX80 S2, DX90 S2
ETERNUS DX400 S2 series