RAID 10

RAID 10 uses mirrored pairs to redundantly store data.

The array must contain an even number of disks. Two is the minimum number of disks that you need to create a RAID 10 array. A two-disk RAID 10 array is equal to a RAID 1 array. The data is striped across the mirrored pairs. For example, a RAID 10 array of four disks would have data written to it in the following pattern:

Figure 1. RAID 10

RAID 10 can tolerate multiple disk failures. If one disk in each mirrored pair fails, the array is still functional, operating in degraded mode. You can continue to use the array normally because for each failed disk, the data is stored redundantly on its mirrored pair. However, if both members of a mirrored pair fail, the array will be placed in the failed state and will not be accessible.