SHARKOON 8-Bay RAID-Station - Manual (Page 23)

8-bay raid station 23
Advantage/disadvantage:
The R30 mode uses less capacity for protection and is the preferred method to reduce
the cost per megabyte for larger installations.
In exchange for low overhead necessary to implement protection, the R30 mode
degrades performance for all write operations. The parity calculations for R30 mode may
result in write performance that is somewhat slower than the write performance to a
single drive.
The resulting storage capacity of the virtual R30 volume will be “n minus 2”-times
(n=number of disks) of the smallest drive.
If one drive fails, the virtual R30 volume is still usable. When the offline drive comes back
online, the appliance begins a rebuild process immediately to restore data redundancy.
During this procedure the LED indications will notify you that a rebuild is in progress.
Notes:
Although the volume remains available during the rebuild process, the volume is
susceptible to data loss through damage to the remaining drive until redundancy is
restored at the end of the rebuild and verification process. Host access takes precedence
over the rebuild process. If you continue to use the virtual R3 volume during the rebuild,
the rebuild process will take a longer time to complete, and the host data transfer
performance will also be affected.
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