Netgear ReadyNAS 102 User Manual

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Volume Configuration
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 ReadyNAS OS 6.1
RAID 5. This RAID level also provides data redundancy, but it requires at least three 
disks. RAID 5 uses the capacity of one disk to protect you from data loss if one disk fails. 
Your data is distributed across multiple disks to improve disk performance. The total 
capacity of your storage system equals the capacity of all your disks minus the capacity 
of one disk. It is supported on systems with at least four drive bays.
RAID 6. This RAID level can recover from the loss of two disks. Your data is distributed 
across multiple disks to improve disk performance. The total capacity of your storage 
system equals the capacity of all your disks minus the capacity of two disks. It is 
supported on systems with at least four drive bays.
RAID 10 (or 1+0). This RAID level uses both RAID 1 and RAID 0 technology. First, your 
data is duplicated so that exactly the same data is stored on two or more disks. Then, the 
data is distributed across additional disks to improve disk performance. It is supported on 
systems with at least four drive bays.
The Flex-RAID levels that you can select depend on the number of disks included in the 
volume. The following table describes the Flex-RAID levels that are available for a given 
number of disks. It also indicates whether adding a disk for data protection is possible for 
each configuration.
Table 1.  Flex-RAID levels and data protection
Number of Disks 
per Volume
RAID Level
Can I add a disk for data protection?
1
RAID 1
Yes. (Additional disk provides redundancy.)
1
JBOD
No. (JBOD is available only for volumes consisting of one disk)
2
RAID 1
No. (Volume protection is already redundant.)
2 or more
RAID 0
No. (RAID 0 does not offer protection.)
3 or more
RAID 5
Yes. (Additional disk provides dual redundancy and converts the volume to 
RAID 6.)
4 or more 
(even number)
RAID 10
No. (Volume protection is already redundant.)
4 or more 
RAID 6
No. (Volume is already protected with dual redundancy.)
Manage Volumes
This section discusses volume management on your ReadyNAS system. You can add or 
delete volumes from the system. Additionally, you can change the volume’s RAID mode and 
level. This section also covers volume status, volume maintenance and volume protection. In 
addition to volume topics, this section also covers extending the storage capacity on you 
ReadyNAS system.