RAID 50

 

RAID 50 provides the features of both RAID 0 and RAID 5. RAID 50 includes both parity and

 

disk striping across multiple drives. RAID 50 is best implemented on two RAID 5 disk arrays with

 

data striped across both disk arrays. RAID 50 breaks up data into smaller blocks, and then stripes

 

the blocks of data to each RAID 5 raid set. RAID 5 breaks up data into smaller blocks, calculates

 

parity by performing an exclusive-or on the blocks, and then writes the blocks of data and parity to

 

each drive in the array. The size of each block is determined by the stripe size parameter, which is

 

set during the creation of the RAID set.

 

RAID 50 can sustain one drive failure per RAID 5 array and still maintain data integrity. For

 

example, the RAID 50 configuration in the graphic below has two RAID 5 arrays. It can survive

 

two drive failures, as long as the failed drives are in different RAID 5 arrays.

Uses

RAID 50 works best when used with data that requires high

 

reliability, high request rates, and high data transfer and

 

medium to large capacity.

Strong Points

RAID 50 provides high data throughput, data redundancy,

 

and very good performance.

Weak Points

Requires 2 to 4 times as many parity drives as RAID 5.

Drives

Six to 32

24MegaRAID Enterprise 1600 Hardware Guide