User manual

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data protection. A minimum of 3 hard disks are required to create a RAID 5
group. The total capacity of the RAID 5 group is equal to the size of the disk
with the smallest capacity in the array times the number of (hard disk – 1).
It is recommended (though not required) that only hard drives of the same
brand and capacity are used to establish the most efficient hard drive
capacity.
In addition, if your system contains four disk drives, it is possible to use
three drives to implement a RAID 5 data array with the fourth drive kept as
a spare disk. In this configuration, the system will automatically use the
spare disk to rebuild the array in the event of a physical disk failure. A RAID
5 configuration can survive one disk failure without losing any system
functionality. When a disk fails in RAID 5, the disk volume will operate in
the "degraded mode". There is no more data protection at this stage, and
all the data will be lost if the unit suffers a second disk failure. A failed disk
should be immediately replaced. Users can choose to install a new disk after
turning off the server or hot-swap the new disk while the server is running.
The status of the disk volume will change to "rebuilding" after installing a
new disk. Your disk volume will return to a normal status once the volume
rebuilding process is complete.
Note: To install a new disk when the server is running, first ensure the disk
volume is in "degraded" mode. Or, wait to hear two long beeps after the
disk crashes and then insert the new disk in place of the failed disk.
RAID 6
RAID 6 is ideal for critical data protection needs. To create a RAID 6 group,
a minimum of 4 hard disks are required. The total capacity of a RAID 6
group is equal to the size of the disk with the smallest capacity in the array
times the number of (hard disks – 2). It is recommended (though not
required) to use identical hard drives to establish the most efficient hard
drive capacity. RAID 6 can survive 2 disk failures and the system can still
operate properly.
Note: To install a new disk when the server is running, first ensure the disk
volume is in "degraded" mode. Or, wait to hear two long beeps after the
disk crash and then insert the new disk in place of the failed disk.
RAID 10
RAID 10 is a combination of RAID 1 (mirroring) and RAID 0 (striping),
without parity. RAID 10 is a stripe across a number of disks to provide fault
tolerance and high speed data transfer. The storage capacity of a RAID 10
group is equal to the size of the disk with the smallest capacity in the array