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BMR + Critical Volumes + Workaround RRS feed

  • Question

  • Hi All,

    I, like others, have been perplexed with the occasional issue while trying to create a BMR backup with DPM2010. On some servers, DPM will say that there is not enough space on the volume to create the backup. This is almost always because wsbackup is running with the -allcritical flag, and some file not on the OS volume has been flagged by the SYSTEM VSS writer as a critical file, thus the entire volume containing that file is included.

    So, per the post here:

    http://social.technet.microsoft.com/Forums/en-US/dpmssandbmrbackup/thread/160b5a47-904f-4b48-b11b-b470f187c0ff

    I tried something out:

    In the file: C:\Program Files\Microsoft Data Protection Manager\DPM\bin\Bmrbackup.cmd

    I replaced "wbadmin start backup -allcritical" with "wbadmin start backup -include:c:". This excludes the data drive that has been included by the SYSTEM VSS writer, in the -allcritical selection. The BMR backup runs successfully after this.

    However, will this backup restore? I do not have a test environment to find out at the moment. I obviously do not expect the 2-3 files on the data drive (which have been considered "critical" by WSB) to be backed up by this method, since I deliberately only incude the C:. However aside from them, is this just as good as a BMR backup of the C: only?

    Thanks!

    Monday, October 4, 2010 6:36 PM

Answers

  • Hi,

    That may work fine, but most likely, you have one of more files on another volume that the system writer is wanting to including for BMR backup.  To identify the offending files and paths, from an administrative command prompt run diskshadow.exe - then list writers.  In the output, look at the files list for the system writer and identify the files that are located on any volume other than the C: volume.

     

    Install this hotfix.

     

     

    980794  System state backup error in Windows Server 2008, in Windows Vista, in Windows 7 and in Windows Server 2008 R2: "Enumeration of the files failed"

    http://support.microsoft.com/default.aspx?scid=kb;EN-US;980794

     

    Then using the information from the list writers output - enter the image paths for the offending files to exclude them from the backup.  Once you do this the -allctitical switch should work.

     

    1.

    Click Start , type regedit in the Search programs and files box, and then press ENTER.

    If you are prompted for an administrator password, type the password. If you are prompted for confirmation, provide confirmation.

    2.

    Locate and then click the following registry subkey:

    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SystemWriter

    Note If this registry subkey does not exist, please create it manually.

    3.

    On the Edit menu, point to New , and then click Multi-String Value .

    4.

    Type ExcludedBinaryPaths , and then press ENTER. Note

    5.

    Right-click ExcludedBinaryPaths , and then click Modify .

    6.

    In the Value data box, type all binary paths that should be excluded from the system state backup operation, and then click OK .

    Note The binary paths should be absolute paths. They should not include environment variables (such as %windir%) and should not be enclosed in double or single quoation marks.

    7.

    Exit Registry Editor.

     

    let me know how this went after you test.

     


    Regards, Mike J. [MSFT] This posting is provided "AS IS" with no warranties, and confers no rights.
    Thursday, October 7, 2010 2:52 PM
    Moderator

All replies

  • Hi,

    That may work fine, but most likely, you have one of more files on another volume that the system writer is wanting to including for BMR backup.  To identify the offending files and paths, from an administrative command prompt run diskshadow.exe - then list writers.  In the output, look at the files list for the system writer and identify the files that are located on any volume other than the C: volume.

     

    Install this hotfix.

     

     

    980794  System state backup error in Windows Server 2008, in Windows Vista, in Windows 7 and in Windows Server 2008 R2: "Enumeration of the files failed"

    http://support.microsoft.com/default.aspx?scid=kb;EN-US;980794

     

    Then using the information from the list writers output - enter the image paths for the offending files to exclude them from the backup.  Once you do this the -allctitical switch should work.

     

    1.

    Click Start , type regedit in the Search programs and files box, and then press ENTER.

    If you are prompted for an administrator password, type the password. If you are prompted for confirmation, provide confirmation.

    2.

    Locate and then click the following registry subkey:

    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SystemWriter

    Note If this registry subkey does not exist, please create it manually.

    3.

    On the Edit menu, point to New , and then click Multi-String Value .

    4.

    Type ExcludedBinaryPaths , and then press ENTER. Note

    5.

    Right-click ExcludedBinaryPaths , and then click Modify .

    6.

    In the Value data box, type all binary paths that should be excluded from the system state backup operation, and then click OK .

    Note The binary paths should be absolute paths. They should not include environment variables (such as %windir%) and should not be enclosed in double or single quoation marks.

    7.

    Exit Registry Editor.

     

    let me know how this went after you test.

     


    Regards, Mike J. [MSFT] This posting is provided "AS IS" with no warranties, and confers no rights.
    Thursday, October 7, 2010 2:52 PM
    Moderator
  • Hi Mike,

    Thank you very much for your feedback.

    My concern with your method is that it seems more complicated than simply telling the bmrbackup.cmd to backup the C:. Here's an example from one of my servers - the system writer is picking up on several hundreds of files on the C: when running vshadow -wm2, which of course is expected. However it picks up on three random files from the D:, which also has applications installed on it but nothing that I, as the systems administrator, deem critical. It is simply not feasible for me to include my entire D: in my BMR backup, nor can I  reinstall the offending application on the C:.

    What I need out of these BMR backups is the ability to restore a functioning Windows OS - if one or two programs don't work because I deliberately excluded them from the BMR backup (for space considerations), that is fine with me. Clearly the best practice for BMR is to have three partitions (at least) - one for the OS, one for the 3rd party applications, and one for data. That way, BMR can suck up the 1st and 2nd partitions but leave the backup of the file/sql/exchange/sharepoint/whatever data on the data drive to DPM's file-level backups.

    From my perspective, if I can do a wbadmin start backup -include:C: and then restore that backup from DPM BMR and get a functioning OS (minus the files that the system writer sees on the D:, of course) ,then that is a totally acceptable solution to me. If on the other hand, this won't yield a functioning Windows OS (say, for example, the -allcritical switch is *required* for any BMR to be bootable), then I am more than happy to test your suggestion. Can you advise?

    Thank you very much!

    Saturday, October 9, 2010 1:48 PM
  • I would suggest you test using the include:c: switch and do a test restore.  The -allcritical is just a shortcut to include all volumes that the system writer reports are volumes to be included in the backup.  If you get an error using the include:c: - then the workround proposed above will need to be performed to exclude the three files on D: volume.
    Regards, Mike J. [MSFT] This posting is provided "AS IS" with no warranties, and confers no rights.
    Saturday, October 9, 2010 3:16 PM
    Moderator
  • Hi Mike,

    I will give this a test at some point this week and let you know. Many thanks!

    Tuesday, October 12, 2010 2:12 PM
  • Mike -- by excluding a path using this registry key, does that exclude it only from the BMR/image based backups, or would it also exclude that path when backing up files or shares?
    Thursday, January 13, 2011 5:05 PM
  • Only BMR/Systemstate backup.
    Regards, Mike J. [MSFT] This posting is provided "AS IS" with no warranties, and confers no rights.
    Thursday, January 13, 2011 5:33 PM
    Moderator
  • Perfect.  Thank you!
    Thursday, January 13, 2011 5:37 PM
  • Hi Mike,

    I was having this problem on three different servers and your solution of using the -include:C: instead of the all critical worked fine on two of the servers. On my AD DNS server however I changed it to the -include:C: as well but I am still unable to backup and getting the same error of not enough space on the volume. I was wondering if you had any other suggestions as to how to check what is being backed up and make sure that I was just backing up the C drive and its important system files. Or also if it was possible to increase the allocated space and thus remove the not enough space warning.

    Thanks,

    Tom

     

    Thursday, February 3, 2011 10:36 PM
  • Hi,

    Just open a command prompt and run the following - when it completes, go to the target share and see how large the backup is.

         wbadmin.exe start backup -include:c: -backuptarget:\\servername\sharename

    Then make sure the DPM replica volume has enough free space, if not, modify the disk allocation and add more.

     


    Regards, Mike J. [MSFT] This posting is provided "AS IS" with no warranties, and confers no rights.
    Thursday, February 3, 2011 10:48 PM
    Moderator
  • Thanks for the quick response.

    I ran the backup and the size was very very large. There is a share on the C drive that has about 400GB of space used in it but it is not critical to the system at all. Is there a way to exclude this folder from the BMR and system state backup?

    If I am able to exclude it then I think the not enough space message would also disappear.

    In DPM I am backing up that shared folder separately from the System State and BMR.

     

    Thursday, February 3, 2011 11:18 PM
  • That would be a question for the windows folks, I'm not sure if wbadmin allows for exclusions.

    Post your question here: http://social.technet.microsoft.com/Forums/en-US/windowsbackup

     

     


    Regards, Mike J. [MSFT] This posting is provided "AS IS" with no warranties, and confers no rights.
    Thursday, February 3, 2011 11:40 PM
    Moderator
  • Thanks for the help.

    I looked it up in bing and it said that exclusions were a part of Windows Server 2008 R2 but not plain Windows Server 2008.  I happen to have just the plain version and so what I am going to do, which isn't the end of the world is add a large secondary drive for just the data share and then leave C to just the system.

    I didn't set the system up but hopefully this will make everything safer and easier to back up overall.

     

    Thanks again,

    Tom

    Friday, February 4, 2011 5:11 AM