Acard ARS-2018 User Manual page 51

ARS-2018/2018E Manual
RAID 1 (Mirroring)
RAID 1 must be composed of hard drives in even number. The RAID controller will
divide the hard drives into a pair, and write data simultaneously into the two hard
drives. The two hard drives contain the same data. When one hard drive's data are
damaged, you can replace the failed hard drive, and the RAID controller will restore
the data by the backup on the other hard drive. For a single hard drive RAID 1 is the
best in fault tolerance.
It is suggested to compose RAID 1with hard drives of the same capacity. Because
the capacity of mirrored disk array is that of the smallest hard drive. For example, a
100GB hard drive and a 120GB one unite into RAID 1. The total capacity is 100GB.
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