Operation Manual

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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 replaced immediately. 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 be sure the
disk volume is in the “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 6
The RAID 6 group 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 the 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) that only hard drives of the same
brand and capacity are used 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 be sure the
disk volume is in the “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.