Promise Technology Network Device EX8654 - Manual (Page 240)

SuperTrak EX Series User Manual
226
RAID 50 – Striped Distributed Parity
RAID 50 combines both RAID 5 and RAID 0 features. Data is striped across
physical drives as in RAID 0, and it uses distributed parity as in RAID 5. RAID 50
provides data reliability, good overall performance, and supports larger volume
sizes.
Figure 7. RAID 50 is a combination of RAID 5 and RAID 0
The data capacity RAID 50 logical drive equals the capacity of the smallest
physical drive times the number of physical drives, minus two.
RAID 50 also provides very high reliability because data is still available even if
multiple physical drives fail (one in each axle). The greater the number of axles,
the greater the number of physical drives that can fail without the RAID 50 logical
drive going offline.
Component Minimum Maximum
Number of Axles 2 16
Physical Drives per Axle 3 16
Physical Drives per Logical Drive 6 256
Distributed Parity
Physical Drives
Data
Stripe
Axle 1
Axle 2