4
Fault tolerance methods
RAID 0
RAID 0 does not support fault tolerance. As shown in Figure 5, RAID 0 configuration provides data
striping, but there is no protection against data loss when a drive fails.
Figure 5 RAID 0
Application scenarios
RAID 0 is useful for rapid storage of large amounts of noncritical data (for printing or image editing,
for example) or when cost is the most important consideration.
Advantages
Has the highest write performance among all RAID methods.
Has the lowest cost per unit of stored data among all RAID methods.
All drive capacity is used to store data (none needed for fault tolerance).
Disadvantages
All data on the logical drive is lost if a physical drive fails.
Cannot use an online spare.
Can only preserve data by backing it up to external drives.
RAID 1
RAID 1 is also called drive mirroring. As shown in Figure 6, P1 and P2 represent two physical drives,
and they form a logical drive. Each data block is duplicated to a second drive and saved on two
drives.
To Next Page
Loading...
Need help?
General
