First Published: 12/12/2008       Last Modified: 12/12/2008      Last Modified by: LL    Article ID:2

Products Affected:   HDPro & HDPro2, HDOne, CalDigit RAID Card, HDElement

In RAID 5, the storage capacity will be 12.5% less than the total capacity. In RAID 6 will be 25% less than the total capacity. There are different schemes for different types of data safety and recoverability. For example, RAID 5 essentially spreads the data across all drives using parity so that if any single drive fails you won't lose any data. Because of this scheme, RAID 5 has n-1 drives storage capacity, you use one drive capacity to save the parity information. RIAD 6 uses n-2 scheme. The parity information for any given block of data is placed on TWO drives seperate from those used to store the data itself. This is to protect your valuable data even in the event that two drives fail.

Keywords : RAID 5, RAID 6, capacity