Appendix C RAID
14
(1) RAID0
This method slices data (send from the host) in a striping size and distributes the data to the
physical disks of the RAID.
If processing is performed concurrently for the physical disks of the RAID, the data transfer time
is reduced to 1/(number of PDs) and data can be accessed quickly. Since RAID0 has no
redundant data, 100% of the disk capacity is available. However, data cannot be accessed when
even a single disk fails.
<Advantage>
y Quick access
y Highest availability of the disk capacity
<Disadvantage>
y RAID0 has no redundant data. Thus, it is inaccessible when even a single disk fails.
y Since more than one physical disk is used, reliability becomes 1/number of PDs.
Since RAID0 has no redundancy, all the data is lost when even a single disk fails. iSM does not
recommend RAID0. Use another RAID configuration.
Data Sent from Host
S
t
r
ip
e
1
S
t
r
ip
e
2
S
t
r
ip
e
3
S
t
r
ip
e
4
S
t
r
ip
e
5
S
t
r
i
pe
1
S
t
r
i
pe
4
S
t
r
i
pe
2
S
tr
i
pe5
S
t
r
i
pe
3
Striping Size
Physical Disk1
2
3