Brain trust question: Buffalo NAS RAIDS?
 

OK, I need help from the brain trust. We have three Buffalo Network storage RAIDS. Two of them have been flawless for many long years. The newest one is making me very frustrated.

The problem child is a Terrastation TS-8VH24TL/R6 which was setup as RAID5. Everything was working fine. It had the latest Firmware update as of last month. Last week one of the eight 3TB drives failed. OK, no big deal, just replace it with a replacement identical drive. While that one was trying to rebuild another drive failed. Oh crap.

The rebuild failed and now the RAID will not mount. We can see the name of the RAID and the 6 drives are all happy, but it will not mount and rebuild.

Tech support for Buffalo is useless. Apparently if the unit is not in warranty they will not even talk to a customer. I have dug around on various forums and found one possible thread of help but it involves a flavor of Unix called Knoppix. I downloaded the DVD ISO image, burned a DVD and then built a boot thumb drive of Koppix 7.6

http://forums.pelicanparts.com/uploa...1456929900.jpg

This is what I see. The one Seagate drive is actually a 3000 Gig or 3 TB drive. Knopix see it as a 5.1 GB drive. with several partitions. Window only can see some partitions and no data at all, so Knoppix or some flavor of Unix is necessary.

If I try to open any of the other partitions in Knoppix I get this:

http://forums.pelicanparts.com/uploa...1456930187.jpg

So back to the first picture. The files that are boxes are some sort of compressed file. Is my data in there? This is drive #2 which I picked at random. It is one of the drives that is working. I can't open those compressed files with anything I have now

Am I just wasting my time here or or is there a way to recover any of the data on the six remaining drive? Any and all helpful suggestions will be welcome.

I'm going to assume the NAS has a built in hardware RAID controller?

If there is a hardware problem with the controller what you need is an identical enclosure (or enclosure with the same exact controller) to be able to read the parity information off the discs.

Are either of the other two the same device?

I really thing the RAID hardware is OK. It just can't read the two defective disk drives and can't rebuild now. I can get the RAID to turn on and boot, but after it gets done checking all the drives it come up with a can't mount the raid error.

The other two RAIDs we have are just 4 drive units and not the same as the 8 drive unit.

BTW, it's only seeing that RAID set as being comprised of 3 drives.

Accounting for parity three 3GB drives will get you a ~5.5TB volume.

Yeah, see my previous comment.

Something about how the RAID set is being seen appears to be the issue.

I think your problem is you had two simultaneous failed discs which is not good.

Need to noodle this some but you may be in for a bumpy ride.

http://forums.pelicanparts.com/uploa...1456933787.jpg

It will boot up and all 8 drives are seen as not defective but two of them are brand new. If I out back in the old failed drive of course it just reads it as defective and the drive light is red.

http://forums.pelicanparts.com/uploa...1456933882.jpg

Withing a few minutes the blue happy screen goes away.

http://forums.pelicanparts.com/uploa...1456933919.jpg

I will keep digging. There must be some way to read some of the data.

Which is the problem with the striped RAID5. If you lose more than one drive, the data is effed. I prefer RAID1 for this reason AND I still backup those drives! I accept the loss of space.

One solution, you might use a utility to clone the bad drives and then try inserting the clones to see if you can access the data.

2 drives going bad in a short period of time on a new NAS would make start to look at power or heat issues. Or more likely, replacing the entire NAS.

Tell us you have a backup of the data!!

Your data is gone.

RAID is all about high availability and is not a backup system. RAID5 is really a not all that great to use unless you fully aware of the potential problems AND you make regular backups of the data.

RAID6 is better but you will soon have similar problems to deal with:

Why RAID 5 stops working in 2009 | ZDNet

Personally, I would go RAID10.