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RAID 1 (MIRRORING)
RAID 1 (Mirroring) consists of at least two drives storing duplicate copies of the
same data. In this mode, the data is simultaneously written to two disks. Thus,
the storage capacity of a two-disk array is combined into a single disk and the
capacity is limited to the size of the smallest disk.
To rebuild, the Target hard drive should be added as the “Spare”. After the RAID
System recognizes the target hard drive, the rebuild process will begin when the
hard drive LED starts blinking.
Under Mirroring mode, only 2 hard drives are allowed without limitations on
the slot location. However, the rest of the hard drive slots are free to perform
under other RAID Modes (requiring 1 or 2 hard drives) using the Advance Mode
Menu.
RAID 1
Disk 1
Disk 2
A
B
C
D
A
B
C
D
In Mirroring mode, if one of the disks fails, either source or backup, the data
is still available. However, if the source disk fails during the rebuild process, the
data in both disks will be lost.
It is NOT recommended to do
hot swap
for the source disk during the
rebuild process because the data in both disks will be lost.