User`s manual

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2.4 R0 MODE
The R0 MODE storage policy distributes access across all hard disks. R0 MODE presents the best data speed but no data
redundancy. R0 MODE storage policy accelerates hard disk drive operating speed by using many disks in parallel. Hard disk
drive data segments are written to different disks simultaneously which increases performance while sacrificing data
redundancy.
To implement the R0 MODE storage policy, the ELITERAID ER104UT(-B) Storage creates a single virtual volume that is
striped across both hard drives, with a storage capacity that is five times of the smallest drive.
2.5 R1 MODE
The R1 MODE storage policy stores all data in duplicate on separate drives to protect against data loss due to drive failure.
One drive mirrors the other at all times. Every write operation goes to both drives. R1 MODE provides the highest level of
data protection for critical data that you cannot afford to lose if a hard drive fails, but halves the amount of storage capacity
because all data must be stored twice. The resulting storage capacity of the virtual R1 volume will be equivalent to the size
of one hard drive (if both drives are the same) or the smaller of the two drives (if they are different).
If one drive fails, the R1 volume is still usable, but it is in a vulnerable state because its mirrored hard drive is inaccessible.
When the offline drive comes back online, the appliance begins a rebuild process immediately to restore data redundancy.
A message appears in the LED indicator to notify you that a rebuild is in progress.
ER104UT(-B)
ER104UT(-B)