Hard disk indicator
1. Red: The hard disk is faulty or is restoring data.
2. Blinking green: Reading or writing data.
3. Off: No hard disk detected.
4.Off: The HDD LED’s blink for about 10s and off when there
is no data transfer via D2-310.
http://dl.tcloudme.com/en/TerraMaster_User_Manual_for_D2-310_en.zip
Und mehr sagt dir das Display beim GR3680-SB3 auch nicht wirklich...
If one of the hard disks becomes faulty while the product is in RAID1, you can replace the faulty hard disk, and
data will be automatically recovered.
Note: While you are replacing the faulty hard disk, this product needs to remain powered on and connected
to the computer. The capacity of the new hard disk should be larger than or equal to that of the faulty hard
disk. The amount of time that data recovery takes depends on the capacity of the hard disk. It ranges from a
few hours to tens of hours. The product and the computer need to remain powered on during data recovery.
Das gilts dabei nur zu beachten.