7
Chapter 1 Introduction
RAID LEVELS (CONT’D)
RAID LEVELS (CONT’D)
RAID Level 1 : “ Disk Mirroring “ High Data reliability
RAID level 1 provides both very high data reliability and continued data availability in the event
of a failure of an array member. When a RAID level 1 member disk fails, array management
software simply directs all application requests to the surviving member.
RAID level 1 is suitable for data for which reliability requirements are extremely high, or for data
to which high performance access is required, and for which the cost of storage is a secondary
issue.
Figure: Disk Mirroring
Optional
Disk 1
Physical
1
2
3
Data
1
2
3
4
5
6
7
8
9
10
11
12
Disk Array Controller
Array Management Software
Provides Logical to Physical Mapping
Disk 2
Disk 3
Disk 4
1
2
3
1
2
3
1
2
3
