Chapter 4 Managing Your Storage; Raid Arrays - Buffalo TeraStation 5000 User Manual

Chapter 4 Managing Your Storage

RAID Arrays

TeraStations support many types of RAID. The type of RAID arrays available for use depends on how many drives are
installed in your TeraStation.
TeraStation
TS5800D
TS5600D
TS5400D
TS5400R
TS5200D
Notes:
• If you change the RAID mode, all data on the array is deleted. This is true for every procedure in this chapter.
Always back up any important data before performing actions that affect your RAID array.
• After the RAID mode is changed (except when creating a RAID 0 array or JBOD), the TeraStation performs a
RAID check that will take about 10 hours per TB. File transfers are slower during this period. While the mes-
sage "RAID I17 ARRAYx Resyncing" is displayed on the LCD panel, do not turn off the TeraStation. If you do, the
RAID check starts over.
• If the TeraStation is restarted or shut down while changing the RAID mode, the message displayed on the
LCD panel changes from I46 or I47 to I18.
RAID 6
*
RAID 6 arrays are available for TeraStations with 4 or more hard drives. RAID 6 combines 4 or more drives into a
single array. The usable space is equal to the sum of the capacity of all drives minus the capacity of two drives. For
example, if 4 drives are combined into a RAID 6 array, the usable space is the sum of the capacity of 2 drives. If 2
drives in the array are damaged, you can recover data by replacing them. If 3 or more drives are damaged, your data
is lost.
RAID 61
***
RAID 61 arrays are available for TeraStations with 8 or more drives. In this mode, two RAID 6 arrays are mirrored in a
RAID 1 array. 8 drives in a RAID 61 array have a usable capacity of 2 x the capacity of the smallest drive.
RAID 60
***
RAID 60 arrays are available for TeraStations with 8 or more drives. In this mode, two RAID 6 arrays are combined in a
RAID 0 array. 8 drives in a RAID 60 array will have a usable capacity of 4 x the capacity of the smallest drive.
RAID 5
*
RAID 5 arrays are available for TeraStations with 3 or more hard drives. RAID 5 combines 3 or more drives into a
single array. The usable space is equal to the sum of the capacity of the hard drives minus the capacity of one drive.
For example, if 4 drives are combined into a RAID 5 array, the usable space is the sum of 3 drives. If one drive in the
array is damaged, you can recover data by replacing the damaged drive. If two or more drives are damaged at the
Default RAID Mode
RAID 5
RAID 1
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