This method has the following benefits:
• Useful when performance and low cost are more important than data protection.
• Has the highest write performance of all RAID methods.
• Has the lowest cost per unit of stored data of all RAID methods.
• All drive capacity is used to store data (none is needed for fault tolerance).
RAID 1 and RAID 1+0 (RAID 10)
In RAID 1 and RAID 1+0 (RAID 10) configurations, data is duplicated to a second drive. The usable
capacity is C x (n / 2) where C is the drive capacity with n drives in the array. A minimum of two drives is
required.
When the array contains only two physical drives, the fault-tolerance method is known as RAID 1.
When the array has more than two physical drives, drives are mirrored in pairs, and the fault-tolerance
method is known as RAID 1+0 or RAID 10. If a physical drive fails, the remaining drive in the mirrored pair
can still provide all the necessary data. Several drives in the array can fail without incurring data loss, as
Hardware issues
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