5 Replies Latest reply on Jul 4, 2012 2:45 PM by a15995

    Broken RAID0 array, help with parameters and ICH9R rom...

    a15995

      Hello!

       

      I'm in sh.. to my neck here. Two weeks ago I lost a harddrive with "cyclic redundancy errors" but managed over a week to salvage 98% of the data on it using third party software. I was happy.

       

      A week later the drive on which I stored the data went down in connection with a BSOD (which is caused by defective ram which I'm about to replace). The problem is that this drive is a RAID0 array of 2TB (2x1TB WD-EADS) but was the only available drive with enough capacity to hold the data. Unfortunately the Win7 Users-folder is also on this volume (using a junction) due to limited space on my SSD system drive.

       

      This was STUPID but I was about to buy two new harddrives in order to get more capacity on external drives and to hold backups etc. Can you believe my luck? It should just have lasted a week more and I would have been in the safe zone...

       

      Anyway, one of the drives in the raid array is labelled as "non-raid" and the status of the raid volume is "failed". I have an Intel ICH9R chipset. I don't think the data is damaged - just the array and maybe the MBR/MFT. A BSOD rarely causes any serious damage in my experience.

       

      I have tried rebuilding a virtual image of the raid volume through third party software using the correct parameters (128KB stripe, offset 63 sectors and the correct order of the drives) but I only get a directory structure with corrupted files in it (however the files are visible). I have put together an excact identical system with the same parameters which I'm typing this message on so the parameters should be correct.

       

      The problem is that one of the drives is still in the raid array and the other volume is just a non-raid disk. I think this might cause problems when rebuilding the virtual volume.

       

      So my question is should I loose the raid drive and make it a non-raid disk in order to do a better scan of the two drives (third party software can put the disks together to form a virtual raid array)?

       

      So the logical question is: in Intel ICH9R rom I have two options - 1 to delete the array and 2 to make the single member disk a non-raid drive. Which should I choose and will either action perform a quick format or just leave the data on it and break the array?

       

      It's very important that the data stays there however fragmented etc. as the third party software should be able to handle this.

       

      Will the data be deleted "physically" (deleting the data on the disk) or only "logically" (deleting the array)?

       

      What is the typical offset of an ICH9R array? I'm pretty sure it is 63 sectors or 31.5KB (which is odd but nevertheless what the identical system is showing)? Will the offset be the same on both disks in the array?

       

      I'm pretty certain that I did this once before - deleting an array and creating a new one - and the data was still there and accessible. But I'm not prepared to gamble anymore (the new array with the new disks will be a 2x2TB mirror - trust me)...

       

      Please help with any experiences when a RAID0 array breaks and the data is intact...

       

      Thanks,

      Søren

        • 1. Re: Broken RAID0 array, help with parameters and ICH9R rom...
          a15995

          ...just a follow-up after reading some more in the community: is the best way to just revert back to AHCI from RAID mode in the BIOS? I'm thinking this may break the array without touching the data?

           

          BTW my rom is Intel Matrix Storage Manager v. 7.5.0.1017 ICH9R...

           

          /Søren

          • 2. Re: Broken RAID0 array, help with parameters and ICH9R rom...
            a15995

            Another followup after succesfully creating a virtual raid array and awaiting 18 hours(!) of backup...

             

            Yes, it is possible as I suspected to recreate a RAID0 array if the disks are intact and only the array is broken. Imagine my relief when I finally saw a complete directory and file structure come alive . I can only recommend the program R-Studio (I have no financial interests in this) mainly due to the fact that it creates a virtual raid in realtime while you set the parameters. You can instantly see, if the parameters result in a working partition on the volume - and in my case the case was closed when I saw the original name of the volume and the NTFS file system.

             

            Many thanks to TGentry in this post. After several unsuccesful attempts I came to realize that the only way to get any further was to reset the remaining disk in the array to non-raid. And despite the warnings no data was affected only the array. The lesson for Intel must be to elaborate a bit on the warning in the window with plenty of room to do this. The warning states that the data will be deleted but this is not true - it is only the array that is deleted.

             

            I know my case wasn't a hard case (retrospectively) but when you loose as much as 2TB of important data you really feel down and I guess the best advice is not to panic. I was ready to pay professionals up to $2,000 to get my data back but luckily this won't be necessary now.

             

            I will return with an update after the backup but next step will be to create an array with the same parameters and disk rotation and hopefully everything will be back to normal without ever needing the backup.

             

            Hope this thread will help someone as unlucky as I was...

            • 3. Re: Broken RAID0 array, help with parameters and ICH9R rom...
              a15995

              Last update:

               

              I seemed to be right about just recreating the raid array after succesfully breaking it.

               

              After creating a new array with the same parameters I tried booting into Windows. No partition was found so I just used the program suggested by TGentry and easily found the original partition again and wrote a new MBR.

               

              After restart I just needed to assign the original driveletter to the volume and restart again. Windows couldn't find my profile but this was easily fixed in the registry by adding .old after the current SID and deleting the .bak part of the original SID (seach Google for this procedure).

               

              After restart EVERYTHING was back to normal

               

              Relieved I quickly made a .bat file which uses robocopy to incrementally backup this important drive to a network disk. Since most of the data was already there because of my previous backup this only took 9 minutes.

               

              Next project will be to make a RAID1 array (2x2TB disks) and just live with this slower setup but since my system is on an SSD I probably won't notice it. I would rather have the security of redundancy.

               

              Again, hope this helps someone...

               

              /Søren

              • 4. Re: Broken RAID0 array, help with parameters and ICH9R rom...
                TGentry

                I'm glad to hear you got it fixed!

                 

                The RAID BIOS command functions could definately be better described, and hopefully that's something Intel has looked at for its more current hardware. If there are any tags you can think of to add to my post/guide which would have helped you find it easier do let me know.

                • 5. Re: Broken RAID0 array, help with parameters and ICH9R rom...
                  a15995

                  Now up and running with 2x2TB ST2000DM0001 disks in RAID1. Lovely 7200 RPM/SATAIII drives delivering ~ 200MB/s in read.

                   

                  I'm pleased to say that this has solved a lot of problem. Most importantly the BSOD's have stopped and was apparently related to striping errors in my RAID0 setup (an endless loop of problems caused by one of the drive failing). Furthermore I have come to realize that RAID1 in fact is as fast as RAID0 when it comes to read operations (because the data is present on two disks and can be read sequentially but only written in parallel).

                   

                  Also, I forgot to update the firmware on the new drives before making the array. No problem, just used the same procedure as before - resetting disks to non-raid, updating firmware on both drives, recreating the array and finding the "lost" partition again using TestDisk. Works like a charm!

                   

                  I now have two 1TB green drives that can be used to hold non-critical data - one of them will be replaced by WD under warranty.

                   

                  So all in all success after all...