8 Replies Latest reply on Jan 5, 2010 8:13 PM by RIH5342

    Raid 1 Rebuild at 23% After 3 Days?


      I have a three-year old Dell Dimension ES520 with two Western Digital 250GB drives set up in a RAID 1 configuration using an Intel ICH8R/DO/DH SATA RAID Controller. I am running XP Professional SP3. This is a basically a stock out-of-the-box Dell setup.


      Three nights ago, a message popped up saying that the RAID volume was degraded. After I rebooted the computer, it immediately began a rebuild. Now, after almost three days, the rebuild is plodding along at 23% complete and I have an unusable computer. I say unusable because since the rebuild begain, overall system performance has dropped to almost nothing with the computer perodically freezing up during the rebuild process. At this rate, I assume I'll be watching the Rose Bowl by the time the rebuild completes.


      My questions are:


      1) Is it normal for a rebuild to take this long? In other words, is this slow performance indicative of another problem? The status screens say my drives are fine and functioning normally.

      2) Are there any configuration changes I can make to speed up the rebuild process?

      3) If my situation is indeed normal, then I am not sure I want the overhead of this happening again. The Dell configuraton utility shows an option to delete the RAID array. My questions:

      a) Can I invoke this option with the rebuild partially complete?

      b) Will I wipe out my hard drive data if I invoke the option to delete the RAID array while the rebuild is running?

      c) What are the implications of deleting the RAID configuration after the rebuild completes? Will I be able to reconfigure the second hard drive as an additional drive on which I can store programs and data files?


      Thanks in advance for any guidance. Any advice and suggestions will be appreciated. I have never dealt with an issue like this before.

        • 1. Re: Raid 1 Rebuild at 23% After 3 Days?

          Do you have any anti-virus SW running? Scanning every block during a rebuild will slow it down.

          1 of 1 people found this helpful
          • 2. Re: Raid 1 Rebuild at 23% After 3 Days?

            Thanks for the tip. However, I have the computer running in Safe Mode with the AV program shut down.

            • 3. Re: Raid 1 Rebuild at 23% After 3 Days?

              Well, it's day 4 and the rebuild is at 30%. I am ready to kill this process. Any suggestions or how-tos would be appreciated.

              • 4. Re: Raid 1 Rebuild at 23% After 3 Days?

                Raid 1 is a mirror so the computer ought to run fine with 1 disk.

                One disk is probably marginal, so during the rebuild, the OS rereading and rewriting until it suceeds.


                Try looking at the event viewer to see if any errors or warnings show up to learn which disk is bad.


                Power down and disconnect the power and the data cable to 1 disk, reboot.

                When booting with one disk good disk, the response should be normal.

                The computer performance with the bad disk should be slow.


                Backup your data ASAP.


                Replace the bad disk with an identical disk, and let it rebuild.


                Good luck.

                • 5. Re: Raid 1 Rebuild at 23% After 3 Days?

                  Thank you VERY much for the suggestion and information on systematically testing each drive. You hit the nail on the head. One of the drives had failed and the system was unable to boot from it. The system is performing far better now on just the one functioning drive than it has for quite some time. This leads me to believe the the failed drive was in a state of decline for quite a while. I think it's a shame that the Storage Manager software cannot accurately detect and report the status of a failed member in an array.


                  Now, the next challenge is going to be finding an identical replacement drive. My current drives are WDC Model WD2500JS and it looks like they are available only from a few suppliers via mail order. But, at least they are available.


                  Thanks again for taking the time to offer your suggestions. Happy New Year.

                  • 6. Re: Raid 1 Rebuild at 23% After 3 Days?

                    I'm glad you're up and running.

                    A raid system buys you time to recover but also increases your chances of a disk failure.

                    When I buy a raid system, I get at least 1 additional disk.

                    It's expensive but way easier to recover when things go wrong.

                    • 7. Re: Raid 1 Rebuild at 23% After 3 Days?

                      Hi. Just a quick followup on my failed drive/lengthy rebuild issue. The rebuild of the new 250GB drive took one hour and twenty minutes. Hopefully, this will provide a useful benchmark for someone..


                      RIH5342, thanks again for the helpful guidance.

                      • 8. Re: Raid 1 Rebuild at 23% After 3 Days?

                        Hey. One more thing, do a disk scan.


                        From the explorer, right click on the drive, select properties, then select all the checks for the file system and disk.

                        It'll do a scan the next time it boots, be prepared for it to take a long time.


                        Backup your data before doing this.


                        If it runs okay, then you can be confident that the OS and the raid are okay.


                        It's much better to find out now that something is wrong than later.