FAQ - Frequently Asked Questions - Knowledge Base

[NT2 U31C] How to replace a faulty drive in a RAID 1 set?

When a drive fails, the corresponding LED lights up red. If only one drive is defective and the RAID mode is set to RAID 1, the data can still be accessed but we recommend to first backup all data in a different location and then replace the faulty drive immediately. If more than one drive at the same time fails, all data is lost.

Method 1 (Recommended)

  1. Backup all the data from the good drive and store the files in a different location.
  2. Turn off the power, disconnect the USB cable and replace the faulty drive.
  3. Turn on the power but do not connect the USB cable yet.
  4. Press and hold the “Set RAID” button for about 5 seconds until all LEDs flash once.
  5. Press the button multiple times until you have selected Non-RAID.
  6. Press and hold the “Set RAID” button for about 5 seconds until all LEDs flash once to set the new RAID mode.
  7. Connect the USB cable to your computer and format the disks as two independent volumes.
  8. Turn off the power and disconnect the USB cable.
  9. Turn on the power but do not connect the USB cable yet.
  10. Press and hold the “Set RAID” button for about 5 seconds until all LEDs flash once.
  11. Press the button multiple times until you have selected RAID 1.
  12. Press and hold the “Set RAID” button for about 5 seconds until all LEDs flash once to set the new RAID mode.
  13. Connect the USB cable to your computer and format the disk.
  14. At this point, you should have a brand new RAID 1 set and you can restore the data from your backup location.

Method 2

  1. Backup all the data from the good drive and store the files in a different location.
  2. Turn off the power, disconnect the USB cable and replace the faulty drive.
  3. Turn on the power and connect the USB cable. The data is mirrored automatically from the good drive. During this process, the HDD LED pulses slowly. The time it takes to complete depends on the drive capacity.

Important

It's always best to keep a copy of your data in a second location. If anything happens to your RAID set, the data gets corrupted or the rebuild fails, you can restore the data from your secondary backup location.

When using the automatic rebuild function, please keep in mind that even if you have stored only a few files on the disk, it might take a whole day to complete the rebuild, because the time it takes to complete depends on the capacity of the drives. For this reason, we recommend using method 1 and starting from scratch.