RAID Levels: Dell PowerEdge Expandable RAID Controller
RAID Levels: Dell� PowerEdge� Expandable RAID Controller
RAID Levels Supported | RAID 10
| RAID 30 | RAID 50
The RAID levels are the model configurations of disk arrays for fault
tolerance and enhanced performance. Each logical drive in a RAID system embodies a RAID
level. Each RAID level has a set of feature and performance tradeoffs. The RAID controller
supports the following RAID levels.
| Raid Level |
Description |
Application |
Disk Drives Needed |
| 0 |
Data is divided into blocks and distributed
sequentially among disks (pure striping). |
Data collection from external sources at very
high transfer rates. Fault tolerance is not required. |
1 or more |
| 1 |
Data written to one disk is duplicated to
another disk (pure mirroring). |
Read-intensive, fault-tolerant systems. |
2 |
| 3 |
Disk striping with dedicated parity drive. |
Noninteractive applications that process large
files sequentially and require fault tolerance. The parity disk is the third drive. |
At least 3 |
| 5 |
Disk striping with distributed parity. |
High read-request rates and low write-request
rates, such as transaction processing, office automation, and online customer service
requiring fault tolerance. |
At least 3 |
| 10 |
Striping of mirrored arrays, a combination of
levels 1 and 0. |
Data storage that justifies the 100%
redundancy of mirrored arrays and needs the enhanced I/O performance of striped arrays. |
4 |
| 30 |
Striping of 2 or more RAID 3 arrays. RAID
level 30 is a combination of 3 and 0. |
Noninteractive applications that process large
files sequentially, requiring fault tolerance and high speed. |
6 |
| 50 |
RAID level 50 is a combination of RAID levels
5 and 0. |
Data that requires highly reliable storage,
high request rates, and high data transfer performance. |
6 |
RAID 10 is a combination of RAID levels 1 and 0. The data is striped
across disks as in RAID 0; each disk has a mirror disk, as in RAID 1 (see the following
figure). This RAID level provides 100% data redundancy through RAID 1 and enhanced I/O
performance through RAID 0 but at a relatively high inherent cost.
RAID 30 is a combination of RAID levels 3 and 0. RAID 30 provides high
speed and data reliability.
The simplest implementation of RAID 30 would use 2 RAID level 3 arrays
and stripe data across them (see the following figure).
RAID 50 is a combination of RAID levels 5 and 0, providing data
reliability and enhanced performance through RAID 5 as well as an additional performance
enhancement through RAID 0.
The simplest implementation of RAID 50 would use 2 RAID level 5 arrays
and stripe data across them (see the following figure).
| 
