Two weeks ago I finally bought a Thecus N5200 PRO and put 5 x 1 TB disks in it in RAID-5. This is a NAS box recommended to me by some colleagues.
After a week one of the disk started reporting soft SMART errors on disk 4 so I was intending to pull out the disk and change it. However a visit away from home for a few days this week delayed that.
While away, my wife showed a “friend” my new toy. He decided to open the “CD TRAY”, and pulled out disk 3…..
The Thecus got a bit upset about this as you can imagine and started beeping, but no data was lost. When I got in on Thursday night I added the disk back again and it began to rebuild the RAID-5 array, the process scheduled to take 15 hours.
After 6 hours the N5200 started beeping again, declaring the ARRAY damaged and …. away went all my data. Not very encouraging. I checked the disks and they all reported ok with disk 4 still reporting the soft errors but no hard errors.
The Thecus logging (out of the box) is next to useless so I couldn’t see exactly what had happened or what had triggered the raid array to be broken. So about 100 GB of real data lost. Nothing really desparate, mainly some iTunes music, but a major PITA for a box I want to relay on for storage.
Since then I’ve locked all the drive doors to keep children, wives and friends from poking their fingers into my systems and have opened a ticket with Thecus to see if I did things incorrectly. However, I’m a bit concerned by what happened as the whole point of this box is to safely store data for me.
Moral of the story:
- lock all disk drives EVEN at home.
- Add stickers on the box saying DO NOT TOUCH
- Test/burn in the drives first to make sure they are in good order before you start
- Test recovery procedures before using the system in real life.
- RAID-5 repair seems more dangerous than you might expect.
Doing all of this type of preparation takes a while and means you can not use the new storage device for quite a while. Perhaps that’s better than losing data. None of this will sound new to anyone in a professional environment but even at home it seems to be necessary.
And I never understand how normal people who just use a USB external disk never seem to have disk failures or problems…
So was I just unlucky?