Dell PowerEdge R830 Integrated Remote Access Controller 8 Version 2.70.70.70 U - Page 184

RAID level 50 - striping over RAID 5 sets, RAID 50 characteristics

Page 184 highlights

• Better read performance, but slower write performance. • Increased redundancy for protection of data. • Two disks per span are required for parity. RAID 6 is more expensive in terms of disk space. RAID level 50 - striping over RAID 5 sets RAID 50 is striping over more than one span of physical disks. For example, a RAID 5 disk group that is implemented with three physical disks and then continues on with a disk group of three more physical disks would be a RAID 50. It is possible to implement RAID 50 even when the hardware does not directly support it. In this case, you can implement more than one RAID 5 virtual disks and then convert the RAID 5 disks to dynamic disks. You can then create a dynamic volume that is spanned across all RAID 5 virtual disks. RAID 50 characteristics: • Groups n*s disks as one large virtual disk with a capacity of s*(n-1) disks, where s is the number of spans and n is the number of disks within each span. • Redundant information (parity) is alternately stored on all disks of each RAID 5 span. • Better read performance, but slower write performance. • Requires as much parity information as standard RAID 5. • Data is striped across all spans. RAID 50 is more expensive in terms of disk space. RAID level 60 - striping over RAID 6 sets RAID 60 is striping over more than one span of physical disks that are configured as a RAID 6. For example, a RAID 6 disk group that is implemented with four physical disks and then continues on with a disk group of four more physical disks would be a RAID 60. 184 Managing storage devices

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Better read performance, but slower write performance.
Increased redundancy for protection of data.
Two disks per span are required for parity. RAID 6 is more expensive in terms of disk space.
RAID level 50 - striping over RAID 5 sets
RAID 50 is striping over more than one span of physical disks. For example, a RAID 5 disk group that is implemented with three physical
disks and then continues on with a disk group of three more physical disks would be a RAID 50.
It is possible to implement RAID 50 even when the hardware does not directly support it. In this case, you can implement more than one
RAID 5 virtual disks and then convert the RAID 5 disks to dynamic disks. You can then create a dynamic volume that is spanned across all
RAID 5 virtual disks.
RAID 50 characteristics:
Groups
n
*
s
disks as one large virtual disk with a capacity of
s
*(
n
-1) disks, where
s
is the number of spans and
n
is the number of disks
within each span.
Redundant information (parity) is alternately stored on all disks of each RAID 5 span.
Better read performance, but slower write performance.
Requires as much parity information as standard RAID 5.
Data is striped across all spans. RAID 50 is more expensive in terms of disk space.
RAID level 60 - striping over RAID 6 sets
RAID 60 is striping over more than one span of physical disks that are configured as a RAID 6. For example, a RAID 6 disk group that is
implemented with four physical disks and then continues on with a disk group of four more physical disks would be a RAID 60.
184
Managing storage devices