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mollari_uk

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Recover data from RAID 5

Hi,

We've recently had a motherboard failure on our server.  How do I get the data off the raid 5 disks?  I'e no idea about Raid disks, so it's probably basic info I'm after.

There were 3 disks on a hardware raid controller.

Not sure if you need more info.

Thanks.
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mollari_uk

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I don't know the exact details, but it came from an HP proliant machine.

If we don't have a replacement server yet, what are my options?
As sirbounty said, some RAID controllers store the array information on the hard drives.  In which case, all you need is to replace the RAID controller with a LIKE controller and the RAID controller's BIOS should be able to read the config off the drives.  While I'm not terribly familiar with HP RAID Controllers, I tend to think they are much like Dell's and that's how Dell's worked.  If it's an old server, consider getting a LIKE server from EBay
Ah - then if it was an internal array controller, you'll need to get those drives in the same order into a system with a like or greater internal controller.
Otherwise, move the drives (again in the same order) and the external controller over to a working server...
Yes, HP/Compaq's Smart Array controllers are much like Dell's.  You'll find that as long as you use the same controller or higher, you should be okay.

And if you're using 3200/53xx series or higher, you will definitely be all set when you get the hardware moved to a working server...
Thanks.  A little bit more info just to clarify:

Because it was a motherboard failure, I'm guessing the controller is ok, and so are the disks.

Our replacement server is Dell, will the HP controller work in the Dell server?

In case you ever need to disconnect drives from the controller, make sure you label which drives are attached to what ports on the controller, so you may reconstruct the configuration exactly as it was.

If the controller is removable (i.e. PCI card), remove controller along with the drives, plug into the another machine and it should be visible there.

You will need appropriate drivers installed on that (working) machine.

In case you use Windows 2000/XP/2003 Dynamic Disks, you may need to "Import foreign disks", which is done in Disk Management (right click My Computer, select Manage, navigate to Disk Management; if you see the disk(s) listed as "foreign", right click, select "IMPORT").

You will then have access to the data (however, the system originally on the RAID, if any, will be unbootable).

If the controller is built into the motherboard, you will need replacement motherboard with the same controller, then attach drives. Check if it works, but do NOT attempt to create, rebuild or initialize the array. The array configuration may be stored on the disk themselves, depending on a controller model/design, if this is a case the replacement controller will pick up the array with no intervention required, or may prompt you to use either "on-disks" or "on-chip" configuration, in this case choose "on-disks".
Remember the #1 rule of data recovery:  STOP !!  Do NOT use the disks in any system where they may be written to.

IF you can find an identical controller, or if the controller is an add-in card (as noted above) that you can just move to another system,  then the array will likely be recognized and you can simply copy the data from it.  Do NOT "initialize" the array.

If that's not the case, the easiest way to recover all of your data is to install all 3 of the disks in some other system along with a drive large enough to hold the data (not hard to do these days with large external USB drives very reasonablyl priced), and then use RAID Reconstructor from http://www.runtime.org/raid.htm
... Note:  If you're going to use RAID Reconstructor you do not need a RAID controller => you simply install the drives in the system on whatever controller (SCSI/SATA/IDE)is appropriate for the drives.   Very easy to use and extremely reliable program.
mollari_uk - I work primarily with HP/Compaq equipment.  If this is an HP system, then you are good to go.  Everything now labeled HP has a workable controller in your scenario.  The config is stored in the controller's BIOS.

That said, you have several options.  The good thing about HP's controller's are, they are very intuitive into the logical disks that exist on your array.  You could easily install these in another server, and the ACU would auto-detect their addition.  Even if you didn't install them in the correct order, the ADU is smart enough to recognize that and would help you order them properly.

Can you provide more detail of where you're going from here?  Are you getting a replacement system board?  Do you have a similiar server available now?  
I've just found out some details about the server:

Server is a ML370, the controller is on board the motherboard.  It is a Compaq smart Array controller 5i.

We're buying a Dell server, as the HP system isn't available anymore.

In that case I'd just use RAID Reconstructor -- easy, quick, and painless (except for the $99 license).
So you had no backup?
The Smart Array (proprietary) in a Compaq is not compatible with a Dell (LSI Logic).
You run a very good chance of hosing everything if you do a straight swap.
Very bad idea.
Go out to Ebay or Price Watch and pick up a used one and recover your data and then move it over to the Dell.
A used 'what'?  An entire server?  The 5i is embedded.  If the system board is what's dead here, you'll need to replace that.  But I do second the query for 'no backup?'
You could purchase an external SA controller, though I don't know how that would work in a non-HP device (only saying that "I" have no experience with it), but you won't get the 5i into another server...
They have external cards for sale.

http://www.chestnutmicro.com/catalog/494
A PCI device is a PCI device.
The only issue you will run into would be drive carriage and the newer Dells have proprietary connections making them a pain to use other peoples HW.
>We're buying a Dell server, as the HP system isn't available anymore.

Not really true.

Any new Proliant will take the disks as long as it has a Smart Array controller inside it and should boot just fine. The array configuration is stored on the disks in the RIS, not on the controller. I presume they're 1" hotplug so a new ML350 G4p or ML370 G4 will take the disks, the smart array will read the RIS on the disks and all should work fine. Alternatively if you want a rack server those same disks should boot fine in a DL380. It's possible you lose a bit of data if you hade the battery backed write cache enabler since it only has 48 hours battery life before the cache gets corrupt.

What happens if you put a HP Smart Array controller into a Dell I don't know except that you'll have a brand new server that neither HP or Dell will support, it's just asking for trouble.

If you post the serial number we can help more since I can identify the exact model from it. Or you can, enter the SN into http://www.compaq.co.uk/warranty/ and the warranty check spits out the part number whether it is in warranty or not.

Alternatively why not get a maintenance company to replace the motherboard for you?
Don't make this too hard.   Simple, quick, and painless:  http://www.runtime.org/raid.htm
... and doesn't matter what the original controller was.   Especially since this isn't really a "broken" array, it will absolutely recover all of your data.
Raid Reconstructor won't even see the drives if you put them on a Dell RAID controller will it? Surely the badged LSI controller would refuse to mount them since it wouldn't be able to understand HP's RIS. Or would you have to hang them off a SCSI controller instead? Just seems a waste to me to pull the data off onto another server and then throw the old working disks away. Hanging HP disks off a Dell isn't going to be simple, quick or painless if they're hotswap.
RAID Reconstructor just needs access to the individual disks -- not mounted as an array.   If the Dell controller won't allow that, then you're correct -- they'd need to be "hung" off a SCSI controller somewhere else;  but I'd think the Dell system would "see" them fine as independent disks.
So buy a new Dell with its own internal disks and install OS. Create one array bigger than the old data as scratch area, create another array to reconstruct the data onto of similar size. Add a SCSI controller to it, connect old disks still in HP server with long internal SCSI cable to HP SCSI backplane (leave sides of machines off), pull raw data from HP disks onto new Dell server scratch area and let Raid Reconstructor make working data on the second array.

Seems a lot simpler to just plug the old disks into a new Proliant.

If "the HP system isn't available anymore" was true then I'd agree with you but I know that to be false.
I used to work for a dat arecovery company and failed raid servers were our bread and butter.

Most important DO NOT PLAY unless you have a backup.

Mark each of the disks as to how it is connected to the dead raid controller

Take each disk and make a full disk image backup - i.e. every single byte - Ghost will do this with the -id switch or you could try one of the other numerous disk imaging utilities including tools such as winhex. If and only if you have got an image copy of each drive then try a replacement controller - if this doesn't work you have your image that you can then slap back down on the drives and either try somethng else or send it to a professional.
We did have a backup, but some data weasn't backed up and it turned out it should have been!

Thanks for everyone's comments.  I'll make sure our IT support company sees them.  I'll award the points ASAP.
If it was them that told you an equivalent Proliant wasn't available I'd change IT company if I was you.