Question

RAID 10+0 Invalid/Missing Disk

Hello everybody. I'm having a problem with my RAID 10+0.

Specs:
2x 3ware 9650SE Raid Controllers;
16x HGST 2TB HDD (8 drives per controller);
Windows Server 2008 R2

Config:
Controller 0 has 8 Drives set as RAID 10 (one unit with 8TB);
Controller 1 has 8 Drives set as RAID 10 (one unit with 8TB);
Windows joining the two units in RAID 0 (stripe) (three logical volumes adding up to 16 TB);

The problem:
We had a power failure and lost 3 drives from Controller 0. Even though they were not part of the same subunit pair (so there was no data loss), the entire unit was set as Inoperable. I contacted 3ware support and they wrote an script to back the controller up to the degraded state. The rebuild occurred successfully and both units show as OK on the controllers.
But the Windows RAID 0 array is broken.
http://i.imgur.com/1Nhfar0.png

Trying to reactivate the disks doesn't do the trick. If I set both Disk 1 and Disk 2 to offline, disconnect the units and then rescan the controllers, the 1st Controller scanned always gives an Online healthy Disk and a Missing Disk on the Server Manager and the 2nd always gives an invalid disk. Doesn't matter which controller (0 or 1) I rescan first, the second to be scanned always gives an invalid disk.

Is there anything I could try to bring this array back up?

Thank you for reading.

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Comments
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Clarification Request
Do You Have a Backup?

First off, do you have a backup of the RAID data? Before you proceed with any more attempts to restore the RAID it's important to know this, as your efforts to go back online can cause further data loss.

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Answer
I'd get back to 3Ware

And make sure they understand your question.

Remember I take it this is for a mission critical system so if all else fails pull out your disaster plan and begin the process your company laid out in case of hard failures like this.

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Waiting for a response

I did get back to 3Ware. The professional that installed our system recon that the script to bring the controller back online might have mess the unit and got the array metadata lost. I'm waiting for 3Ware response, since they have been very helpful so far.

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I see below there was no backup.

For a business that could be the end of times.

Anyhow, google up this "Disaster recovery plan." It sounds like this plan wasn't in the works yet. There are some small shops that just don't want to hear about it.

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Answer
Do You Have a Backup?

I realize that getting the array back online would seem like a good idea, but if you don't have a backup any rebuilding could lead to further data loss, and possibly more drive failures. Is this a situation where you need to recover the data, or are you just trying to get it online so you can restore the backup?

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Data recovery

We are actually trying to recover the data. This is our first experience with large data storage, so we are in the process of learning some basics. If we had a backup we could recreate the array from scratch and restore the data, but unfortunately that is not the case.

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I think it's time for professional recovery

Given that there is no backup, I'd say it's time to consider professional recovery. Trying to put it back online like this is unlikely to work, and it likely to further complicate getting the data back later. What will need to be done is to build a virtual RAID array using images of the original drives and software such as R-Studio to manually determine all the RAID settings and reconfigure it.

Just to give you a baseline of what a recovery like this would run, our company (Data Medics) would charge $5650 for such a recovery. Possibly a bit more if we had to do any clean room work to recover a particular drive.

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Best to seek professional help

In this type of situation, it is not a good time to play with your client's data for a few reasons:

1. You could and likely will make things worse
2. The amount of time you are wasting messing around is money lost for your client during the down time.
3. Your efforts will likely make things more expensive when and if you finally send it to a pro

So, at the very least, make sure your client is 100% aware of the risks of your experimentation.

If you want to learn something, start by getting a full sector-by-sector copy of each drive and then contact your preferred data recovery partner lab to see if they will assist you remotely.

Whatever you do, do not try to recover directly from the original drives and do not try to force the RAID back online.

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