Replace faulty drive in Raid 10 using smaller drive?

Question

I have a Raid 10 array with a faulty drive in a Qnap TS-809.

The array contains the following drives: (I know it was a stupid idea to mix the drives in the first place)

1. 2TB WD Red --\
2. 2TB WD Red --/

3. 2TB WD Red --\
4. 2TB WD Red --/

5. 2.5TB WD Green --\
6. 2.5TB WD Green --/     <-- Faulty Drive

I would like to replace the faulty drive with another WD Red and have a couple of spare WD Red 2TB drives.

As the 2.5TB drives were added to the array made up of 2TB drives, would they be treated as 2TB and therefore would I be able to replace with 2TB drives?

Thanks

Tell me this isn't in a production environment? – Chopper3 Jun 21 '16 at 13:50 — Chopper3, Jun 21 '16 at 13:50

score 1 · Answer 1 · answered Jun 21 '16 at 14:12

1

So long as the 2.5 Tb drives look like 2.0 drive to the array, you should be able to swap it.

answered Jun 21 '16 at 14:12

Jim B

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score 0 · Answer 2 · answered Jun 21 '16 at 13:27

I don't think you can replace with a smaller disk in any kind of raids. Instead you might need to move/copy your data from the functioning disk(s) to the new (smaller) disk and recreate your raid.

On the other hand replacing with bigger disks is possible.

score 0 · Accepted Answer · answered Jun 26 '16 at 10:28

As this may help someone else in the future:

Because the larger disks (2.5TB) had been added to an array that was first initialised with smaller disks (2TB), they are treated as a 2TB disk.

I confirmed this with QNAP tech and replaced the 2.5TB disk with a new 2TB disk. The array has succesfully rebuilt and working fine.

My next step is to replace the other 2.5TB disk with a better suited NAS disk.

Replace faulty drive in Raid 10 using smaller drive?

3 Answers3