RAID Levels: PowerEdge� Expandable RAID Controller 2/SC
RAID Levels: PowerEdge Expandable RAID Controller 2/SC
Select a RAID Level | Factors
to Consider When Selecting a RAID Level
PowerEdge Expandable RAID Controller 2/SC
(hereafter referred to as "PERC 2/SC") supports the
following RAID levels:
| RAID Level |
Type |
| 0 |
Standard |
| 1 |
Standard |
| 5 |
Standard |
To ensure the best performance, you should
select the optimal RAID level when you create a system drive. The
optimal RAID level for your disk array depends on a number of
factors including:
- Number of drives in the disk array
- Capacity of the drives in the array
- Data redundancy requirements
- Disk performance requirements
| Level |
Use |
Pros |
Cons |
Maximum
Drives |
Fault
Tolerance |
| 0 |
Data divided
in blocks and distributed sequentially (pure striping).
Use for noncritical data that requires high performance. |
High data
throughput for large files. |
No fault
tolerance. All data lost if any drive fails. |
1 to 8 |
No |
| 1 |
Data
duplicated on another disk (mirroring). Use for
read-intensive fault-tolerant systems. |
100% data
redundancy. |
Doubles disk
space. Reduced performance during rebuilds. |
2, 4, 6, or 8 |
Yes |
| 5 |
Disk striping
and parity data across all drives. Use for high read
volume but low write volume, such as transaction
processing. |
Achieves data
redundancy at low cost. |
Write
performance not as good as RAID 1. |
3 to 8 |
Yes |
|
