locked
Data Corruption RRS feed

  • Question

  • Hi, I upgraded to the RTM 3 days ago, everything went fine.  2 days ago I copied a large amount of data onto the Home Server from a USB drive.  1 day ago we had a wind storm and the power got knocked out.  The home server was not on a UPS.  Today I noticed that many of the files that I copied are corrupt.  Some are data files which just give errors when I try to load them.  Others are still there but show 0 in file size.  Could a power outage cause something like this?  Even a day after copying the files?

    I stumbled across this thread about random data corruption and I started getting scared....

    http://forums.microsoft.com/WindowsHomeServer/ShowPost.aspx?PostID=2212547&SiteID=50

    Thanks

    Tuesday, October 9, 2007 4:42 AM

Answers

  • Hi, I just thought I'd post a follow up to this thread.

     

    I've been in touch with Microsoft, who were VERY helpful I might add, and they found that parts of my files were filled with zeros.  Most likely a result of the power outage which probably occured as balancing was going on.  Still no idea why the second copy attempt also became corrupted....but it hasn't happened since.  I guess I'll just keep my eyes open for any further problems.

     

    Bottom line, if you're planning on using WHS as a file server, GET YOURSELF A UPS!!!  With the amount of time WHS spends balancing, you're gonna have problems if the power goes out unexpectedly.

     

    Thanks...

    Thursday, October 18, 2007 12:32 AM

All replies

  • The data corruption issue has to do with alternate data streams and file synching programs, probably not your issue.

    Sounds like DEMigrator was working on balancing and got interrupted. Personally I can't imagine a server without a Battery Backup. It sounds like you were copying files so hopefully you still have the original. Go buy a large battery backup and start over.

    Tuesday, October 9, 2007 4:19 PM
  • Did you copy the files to the shared folders, or directly to D:\shares?

     

    Tuesday, October 9, 2007 6:41 PM
  • Hi, here's a bit of further information.  Balancing was turned off for this folder, and I WAS copying to the network share and not to the D: drive directly.

     

    Another scary thing happened.  I deleted all the data which I didn't trust anymore and I recopied the data onto the server from the USB drive.  Most of the files then opened fine.....BUT, there was one Autocad file which still would not open.  I copied that file a third time and it opened fine.   ???  I'm afraid to get home today to see if everything still opens.  At this point I believe that my Windows Home Server is corrupting data and I don't trust it anymore.

     

    I guess the possibility remains that I should not have "upgraded" from RC1 to RTM.  Perhaps I should have done a complete format of both the system drive and the data drive and installed from scratch?

     

     

     

    Tuesday, October 9, 2007 8:53 PM
  • No, you had DUPLICATION turned off... there's no way to turn off Balancing (without manually stopping the service).

     

    What Ken was saying, and I agree with as the probable cause: demigrator service was moving the files around on your drives (this is perfectly normal operations) when the power outage hit.  This caused the files to become corrupted/lost, same as any other copy process that's interrupted.

     

    Tuesday, October 9, 2007 9:08 PM
  • Ok, thanks for the clarification.  I didn't realize that the demigrator service moved files around.  I assumed once they are copied onto the system they would stay put if duplication was turned off.  That could explain the data corruption during the power outage but not the Autocad file which I had to re-copy a third time.

     

    I can pinpoint the exact time of the power outage (my main computer has a UPS that records events), is there a way I can determine if the demigrator was moving files on the Home Server at this time?

     

    Thanks...

     

    Tuesday, October 9, 2007 9:20 PM
  •  Prelector wrote:
    What Ken was saying...
    Ken didn't say it, actually. (You know, Ken hates it when Ken starts talking about Ken like Ken wasn't there. It's hard enough for Ken to have an intelligent conversation with Ken in the first place... Smile )

    Anyway, the file system filter driver and DE don't really move files for the most part, but they do manipulate them and write to them. The end result is the same: a power loss at just the wrong moment can definitely result in data loss.
    Wednesday, October 10, 2007 3:10 AM
    Moderator
  • Suspend,

    Can you please contact whsforum@microsoft.com we would like to further investigate your issue.

    Thanks,

    Mark

    Thursday, October 11, 2007 12:09 AM
    Moderator
  • Hi, I just thought I'd post a follow up to this thread.

     

    I've been in touch with Microsoft, who were VERY helpful I might add, and they found that parts of my files were filled with zeros.  Most likely a result of the power outage which probably occured as balancing was going on.  Still no idea why the second copy attempt also became corrupted....but it hasn't happened since.  I guess I'll just keep my eyes open for any further problems.

     

    Bottom line, if you're planning on using WHS as a file server, GET YOURSELF A UPS!!!  With the amount of time WHS spends balancing, you're gonna have problems if the power goes out unexpectedly.

     

    Thanks...

    Thursday, October 18, 2007 12:32 AM