If too many hard drives fail in an NSM5200 RAID array, loss of data will result.
Pelco Video Management
NSM5200 network storage manager, all versions.
The NSM5200 uses RAID 6 technology to provide dual-parity blocks that are striped across all disks in the array.
Up to two hard drives can fail at the same time on an NSM5200. If more than two hard drives become inoperable, the data on the recorder will be lost.