NetApp RAID-DP (double parity) hard drives prevent 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.