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. The speed of operation is slower in comparison to other RAID modes.
During rebuild, the first HDD inserted into one of the HDD slots is recognized by the RAID
System as the source HDD. To rebuild existing data from a source HDD to a backup HDD (target
HDD), the source HDD must first be inserted into one of the HDD slots. After the host detects
the source HDD, the target HDD should then be inserted in one of the other HDD slot. The RAID
System will then recognize the target HDD and the rebuild process will begin when the HDD LED
starts blinking.
In Mirroring mode, only 2 HDDs are allowed for the function to perform properly.
There is no limitation on the order of insertion or the slot number. However, if all 4
HDDs are inserted, the RAID System can only do Mirroring in the HDDs positioned in
HDD 1 and HDD 2. It is not possible to process two sets of HDDs at the same time.
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 H
ot Swap
for the source disk during the rebuild process
because the data in both disks will be lost.
BIGROC 1S – 4Bay RAID - 1U Rack Mount System - User Manual
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