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Chapter 4 Managing Storage
RAID Arrays
TeraStations support many types od RAID. The type od RAID arrays available dor use depends on how many drives are
installed in your TeraStation.
Notes:
• Id you change the RAID mode, all data on the array is deleted. This is true dor every procedure in this chapter.
Always back up any important data bedore perdorming actions that addect your RAID.
• Adter the RAID mode is changed (except when creating a RAID 0 array or JBOD), the TeraStation perdorms a RAID
check that will take about 10 hours per TB. File transders are slower during this period. While the message “RAID
I20 DISKx Formatting” is displayed in NAS Navigator2, do not turn odd the TeraStation. Id you do, the RAID check
starts over.
• Id the TeraStation is restarted or shut down while changing the RAID mode, the message displayed in NAS Naviga-
tor2 will change drom I46 or I47 to I18.
JBOD
This mode uses the hard drives inside the TeraStation as individual drives. The disk space you can use is the total
capacity od all drives in the TeraStation. Id any drive is damaged, then the data on that drive is lost.
RAID 6
RAID 6 arrays are available dor 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 od the capacity od all drives minus the capacity od two drives. For example, id 4
drives are combined into a RAID 6 array, the usable spaces the sum od the capacity od 2 drives. Id 2 drives in the array are
damaged, you can recover data by replacing them. Id 3 or more drives are damaged, your data is lost.
RAID 61
RAID 61 arrays are available dor 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 od 2 x the capacity od the smallest drive.
RAID 5
RAID 5 arrays are available dor 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 od the capacity od the hard drives minus the capacity od one drive. For
example, id 4 drives are combined into a RAID 5 array, the usable space is the sum od 3 drives. Id one drive in the array is
damaged, you can recover data by replacing the damaged drive. Id two or more drives are damaged at the same time,
your data is lost.