IBM Netfinity ServeRAID-4L Ultra160, Справочник пользователя

Страница: 24 / 114

Understanding RAID level-0
RAID level-0 stripes the data across all the drives in the array. This offers
substantial speed enhancement, but provides no data redundancy. RAID level-0
provides the largest storage capacity of the RAID levels that are offered, because
no room is taken for redundant data or data-parity storage.
RAID level-0 requires a minimum of one drive and, depending upon the level of
firmware and the stripe-unit size, supports a maximum of 8 or 16 drives.
The following illustration shows an example of a RAID level-0 logical drive.
Start with two physical drives.
Create an array using the two physical drives.
Then, create a logical drive within that array.
The data is striped across the drives, creating blocks.
Notice that the data is striped across all the drives in
the array, but no redundant data is stored.
1 2
3
4
5 6
7 8
A physical drive failure within the array results in loss of data in the logical drive
assigned RAID level-0, but only in that logical drive. If you have logical drives
assigned RAID level-1, 1E, 5, or 5E in the same array, they will not lose data.
Note: If you have an array that contains only one physical drive, you can assign
only RAID level-0 to the logical drive in that array.
10
IBM
®
Netfinity
®
: ServeRAID
™
-4L Ultra160 SCSI Controller User’s Reference