RAID level-1 provides 100% data redundancy and requires only two physical drives. With RAID level-1, the first half of a stripe is the original data; the second half of a stripe is a mirror (that is, a copy) of the data, but written to the other drive in the RAID level-1 array.
Because the data is mirrored, the capacity of the logical drive when assigned RAID level-1 is 50% of the array capacity.
The following illustration shows an example of a RAID level-1 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 on the drive on the right is a copy of the drive on the left. |
![]() |
With RAID level-1, if one of the physical drives fails, the ServeRAID controller switches read and write requests to the remaining functional drive in the RAID level-1 array.
See also
Understanding
RAID technology
Understanding
stripe-unit size
Selecting a
RAID level
RAID level-0
RAID level-1
Enhanced
RAID level-5
RAID level-5
Enhanced
RAID level-x0