Volume Shadow Copy Aanomiles RRS feed

  • Question


    If I use the C++ Volume Shadow Copy API to create a shadow copy, that shadow copy does not show up when using the Disk Management Console (viewing the volume properties).  If I use the example program "vshadow", same thing, but if I use vssadmin, the shadow copy WILL show up in Disk Management Console.


    Anyone have any ideas on why this is happening?

    Thursday, May 15, 2008 9:19 PM


All replies

  • For anyone who is interested, I was able to figure this out myself.


    For a shadow copy to be visible to Disk Management Console, it me must "Client Accessible".  Only the System Provider can make shadows that are client accessible, not hardware providers.



    Friday, May 16, 2008 8:13 PM
  • same 2 u

    did u see the document(readme.doc)? page14

    What are the limitations of VSHADOW?


    To keep the sample code small and simple to read, we choose to not implement some advanced requirements of a true VSS requestor. Please see the BETEST sample code from the VSS SDK for a fully-implemented VSS requestor.


    -          VSHADOW does not allow selecting components through the command-line. You must instead specify a set of volumes such that the set of desired components will be automatically selected. Still, you can verify whether a certain set of components is selected using the “-wi” option.

    -          VSHADOW does not contain any file-copying code required by a true backup application.

    -          VSHADOW does not have any VSS backup and restore functionality. Please see the BETEST sample code for a full implementation of a VSS backup/restore application.

    -          The component consistency verification algorithm in VSHADOW has two limitations. Please see the next chapter (Component selection in VSHADOW) for more details.

    o        The algorithm will not follow component dependencies.

    o        The algorithm will not follow mount point chains in recursive file descriptor specifications. VSHADOW assumes that all file descriptors contain data on a single volume.


    A real requestor will have to add additional code to deal with the two scenarios described above. To test your requestor, make sure that you respect all the component selection rules outlined in the latest VSS SDK. Make sure that your requestor works with the VSS test writer, which should exercise these scenarios. Also, you need to test your requestor with all known writers on the targeted SKUs.


    Finally, we should note that VSHADOW only implements minimal restore functionality, assuming that the files are always restored in the same location as during the shadow creation. VSHADOW does not implement some advanced features that are required for a true requestor, like complex restore methods, stopping/starting writer services, rebooting the machine, sub-component selection, alternate targets, etc.


    Monday, June 2, 2008 8:39 AM