ISSUE: Replacing original TeraStation drive with a larger capacity drive
CAUSE: Faulty drive needs to be replaced.
PLATFORM: Terastation NAS
SOLUTION: It can be larger, but not smaller if it's part of a RAID1 or RAID5 array. The extra space in the case of a larger drive won't be added to the total volume of the TeraStation. If a smaller drive is used, Tera will reply with an error when an attempt to rebuild the RAID array. It can be larger but Buffalo Technology do not support this, as there might be no possible useage of the extra space of the drive.
Replacing more then 1 drive can void the warranty and possible make the unit useless.