Running chkdsk with Rollback Rx

Discussion in 'backup, imaging & disk mgmt' started by Aaron Here, Mar 6, 2011.

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  1. Aaron Here

    Aaron Here Registered Member

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    I recently received a pm asking me if I believe it's ok to run chkdsk /f or /r on a system partition under Rollback Rx's 'control'. I replied (in truth, but with intrepidation) that I have not experienced any problems running chkdsk /f or /r on my RB partition. But I'm wondering ...have I been lucky?

    I would like to ask Panagiotis and other RB users if they have encountered any issues running chkdsk /f or /r. Your experiences (or your thoughts) in this matter would be appreciated.

    Aaron
     
    Last edited: Mar 6, 2011
  2. pandlouk

    pandlouk Registered Member

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    On RBRx 8.x and earlier, chkdsk is not recomended. It depends by if the shield driver is invoked before or after the autochk.exe (preboot version of chkdsk.exe) is run and is a gamble (50% chances to go wrong). If the driver is loaded before autochk.exe /f /r is run no broblem; but if autochk.exe /f /r runs before the driver loads and finds the disk dirty(common after power outage or BSOD), you'll encounter the famous chkdsk bug of RBRx.
    Bottomline, Aaron you were very lucky you never had problems (maybe you used RBRx on a laptop?).

    On RBRx 9.x is safe to use chkdsk /f /r, but before running it you should check the registry entries used by Autochk.exe. If you see the following:
    Hkey_local_machine\System\CurrentControlSet\Control\Session Manager\ BootExecute:REG_MULTI_SZ: chkvdisk autocheck autochk *
    is ok to run a chkdsk.exe /f /r. If the string chkvdisk is missing, you should manually repair the registry before runing a chkdsk.exe /f /r.
    (*check the attached image)

    chkvdisk = modified versions of the microsoft "Auto check virtual disk" DDK drivers used (ChkVdiskxp.exe= modified version of winxp, ChkVdisk2k.exe= modified version of win2000 and ChkVdiska64.exe= modified version of win2003 64bit) to perform a autocheck on virtual disks. Instructs windows to load first the virtual disk (RBRx snapshot) and then to run the autocheck in the virtual disk and not on the real system (baseline snapshot).

    Panagiotis
     

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    Last edited: Mar 6, 2011
  3. Aaron Here

    Aaron Here Registered Member

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    Hi Panagiotis,

    Thanks for your definitive explanations and instructions - I do not deny that I may have been lucky re running chkdsk, but I don't see what difference it would it make if I were on my desktop or laptop. o_O

    Aaron
     
    Last edited: Mar 6, 2011
  4. pandlouk

    pandlouk Registered Member

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    You are welcome. :)

    On a laptop you'll never encounter a power outage since you are protected by the battery. If the battery goes low windows will either shutdown normally or hibernate. BSODs very very rarely cause a dirty bit on a disk. So, on a laptop you may never encounter this bug.

    Panagiotis
     
  5. Aaron Here

    Aaron Here Registered Member

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    Panagiotis, I now get what you meant... ;)

    Aaron
     
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