RAID-DP
Providing protection from dual drive failure
Conventional, single-parity, RAID schemes provide protection in the event of a disk drive failure. If a drive fails, the data can still be constructed from the surviving drives and when the failed drive is replaced, the entire array can be rebuilt to its protected status. However, if a second drive should fail before the array is rebuilt then all of the data can be lost. With today's high capacity disk drives, this rebuild time is typically many hours, increasing the probability of a second drive failure before recovery is complete.
NetApp RAID-DP (double parity) technology prevents data loss in the event of a second drive failure without excessive redundancy costs. In an elegantly simple solution, a second parity drive is added to the array and parity for this drive is calculated differently from the first parity drive.
With RAID-DP, your data remains protected even during a recovery rebuild and can even withstand a second drive failure during rebuild. RAID-DP is just one of the ways that the StoreVault S500 delivers peace-of-mind data protection.
RAID-DP is a diagonal parity implementation of RAID 6, as recognized by the Storage Networking Industry Association. RAID-DP means, quite simply, dual-drive parity that can scale without downtime and is not subject to the performance penalties associated with other RAID 6 implementations. [more »]
