User manual

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array. The parity information is distributed and stored across each hard drive. If a
member hard drive fails, the array enters degraded mode. After installing a new hard
drive to replace the failed one, the data can be rebuilt from other member drives
that contain the parity information. To create a RAID 5 disk volume, a minimum of 3
hard drives are required. The storage capacity of a RAID 5 array is equal to (N-1) *
(size of smallest hard drive). N is the number of hard drives in the array.
RAID 6 Disk Volume: The data are striped across all the hard drives in a RAID 6
array. RAID 6 differs from RAID 5 that a second set of parity information is stored
across the member drives in the array. It tolerates failure of two hard drives. To
create a RAID 6 disk volume, a minimum of 4 hard drives are required. The storage
capacity of a RAID 6 array is equal to (N-2) * (size of smallest hard drive). N is the
number of hard drives in the array.
RAID 10 Disk Volume: RAID 10 combines four or more disks in a way that protects
data against loss of non-adjacent disks. It provides security by mirroring all data on
a secondary set of disks while using striping across each set of disks to speed up
data transfers. RAID 10 requires an even number of hard drives (minimum 4 hard
drives). The storage capacity of RAID 10 disk volume is equal to (size of the
smallest capacity disk in the array) * N/2. N is the number of hard drives in the
volume.
Disk Configuration and NAS Models
For disk configuration and applied NAS models, please refer to the table below:
Disk Configuration
Applied NAS Models
Single disk volume
All models
RAID 1, JBOD (just a bunch of disks)
2-drive models or above
RAID 5, RAID 6, RAID 5+hot spare
4-drive models or above
RAID 6+hot spare
5-drive models or above
RAID 10
4-drive models or above
RAID 10+hot spare
5-drive models or above