RAID 5 and data recovery.

hazee

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Jan 8, 2009
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Hi all,

Below are two different questions posted by me and answer of an expert may be. Do you think its the right way to recover the data? Also suggest how I can get two arrays running on one machine.


Question ONE:
I have a DELL Poweredge 2800 with a Raid 5 configrutaion of 3 hard drives capacity 73GB 10k Ultra 320 SCSI. Two of the hard discs started blinking 4 times per second which clearly states the hardware failure in dell systems. So 2 out of the 3 HDs stopped working. Unfortunately, I do not have any backup. :(

I tried to bring the hard drives ONLINE by FORCE option provided in the utility manager to configure RAID and got the hard drives up but couldn't login to windows server 2003. It started showing NTLDR, NTDETECT and ntsokrl.exe missing messages. I also copied the files using recovery console with Windows Server installation CD but still no use and system is not booting up anymore.

How I can recover the data back. Is it possible to get back? I offcourse do not require each and everything stored on the Hard drive but one SQL Server database and a folder of more than 50k employees pictures is very important.

Answer:
Likely you could get the OS running with an "over the top" Win 2003 repair install but this will lessen your chance at data recovery. Personally I would add another disk as a single drive (raid 0 ), get the OS installed on that disk, then pull off any needed data from the original array. If you proceed with the original array restoration, there is a very good chance original data will be over written, due to corruption.

Question TWO:
Can you please provide some basic steps that how should I add a single drive Raid 0? I really dont know how to configure two arrays on one machine and bootup fromt the newly installed and use the old one as secondary.

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Thanks for any help.
 

MrLinux

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You need to know what is failing before trying to rebuild; the chances of two drives failing at the same time is very small, trying to rebuild/force with a faulty controller/power-supply/cable/whatever will just risk more problems.

Ask Dell if there is an approved/specialist engineer in your area and follow his/her advice.
 
Do as the expert suggested. Install a single disk and use the RAID configuration utility to add it to a new RAID0. Then install Windows Server 2003 on that one disk array.

It doesn't make sense not to backup servers until it's too late. I hope it isn't a corporate server that contains valuable information.

Why can't you call Dell? It might cost you (or the owner of that server), but Dell actually know their servers quite well (and so do HP).
 
A broken RAID0 contains a single drive and it works just fine.

You probably shouldn't break the RAID5, but it also shouldn't be your boot array. I'm not familiar with that server and RAID controller, but it normally is possible to define which RAID the server will boot from (boot sequence). Just make sure the new hard disk is the boot disk.

Since a SCSI controller is included, you could also use it and make it the first boot disk instead of connecting an additional disk to the PERC4.
 

navvara

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First, I'm more familiar with IBM servers than Dell servers but this advice should also apply to your Poweredge.

It's more likely that the raid controller, the raid cable or the motherboard ito be bad than it is for two hardrives to fail in short order.
What happens if you plug in a new (or another) hard drive in the same slot that the drives with the PFA are plugged into? Be careful when you do this since your raid card might corupt your array when you do this. If the new (or another, good drive from the array) hardrive still comes gets a PFA when the machine boots up then the problem isn't your hardrives.

Do you still have the CD's the server came with? One of them should say: "Dell™ PowerEdge™ Installation and Server Management
CD". You can use this to add a new raid array or maybe even rebuild your old array to a new one, but I wouldn't trust this to work if your mobo, raid cable or raid controller is bad.

Whatever you do, don't break the raid array unless you can risk data loss. Don't delete anything Professional data recovery will still be able to salvage data if you do but don't expect it to be coherent.

 

hazee

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I have installed a new SCSI, configuered RAID 0 and installed a new OS. System is UP and running. Befor installation I removed the three HDs which were configuered for RAID5.

Now when I connect the three HDs back and try to boot system with the newly installed SCSI it doesnt bring the 3 HDs online(Raid5). Rather it just shows the READY title in Utility Manager.

Now it means I have to recreate array. If I do that I will loose the data. Is there any other way that I can bring these HDs online and I should be able to boot the system with the newly installed HD?

Plz assist.
I have screen shots of the utility manager but I think I cant attach it.

Regards,

 
If your data is very important, you'll have to get an expert involved or send the drives to a data recovery place. You can't recreate the RAID5 without losing data. Since you originally had a working RAID5 before, what broke it?

You have to upload images to a site and then insert the URL.
 

Gatorbait

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Contact DELL or the Manufacturer of the RAID CARD. You can create the RAID5 using the same drives without destroying the data, HOWEVER, DO NOT INITIALIZE THE DRIVES and DO NOT FORMAT THE DRIVES!!!!!! Screen shots would be nice to make sure you do this properly! Best to contact the Manufacture or DELL.
 

BillyDataGuy

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I hope who ever is reading this post looking for help with a RAID 5 recovery makes it down to this post. Or at least takes into consideration the few responses from people who actually seem to care whether or not this recovery case gets solved successfully. If you do not know enough of what you are doing with this type of recovery to understand that re initializing or adding a drive to rebuild the array, or re installing software of any kind can destroy your data, you should not be attempting this level of recovery yourself. If you are unable, or don't have the equipment to accomplish the few simple initial steps found here http://www.sertdatarecovery.com/raid-recovery/raid-5-data-recovery then you definitely need a pro. Don't think otherwise.