ValidateVirtualHardDisk method of the Msvm_ImageManagementService class

Validates whether a virtual disk image can be opened in read-only mode.

Syntax

uint32 ValidateVirtualHardDisk(
  [in]  string              Path,
  [out] CIM_ConcreteJob REF Job
);

Parameters

Path [in]

Type: string

A fully qualified path that specifies the location of the disk image file.

Job [out]

Type: CIM_ConcreteJob

A reference to the job (can be null if the task is completed successfully).

Return value

Type: uint32

This method can return one of the following values.

Return code/value Description
Completed with No Error
0
Method Parameters Checked - Job Started
4096
Failed
32768
Access Denied
32769
Not Supported
32770
Status is unknown
32771
Timeout
32772
Invalid parameter
32773
System is in used
32774
Invalid state for this operation
32775
Incorrect data type
32776
System is not available
32777
Out of memory
32778
File not found
32779
[!Note]
Added in Windows Server 2012 R2.

Vhd differencing chain cycle detected
32787
[!Note]
Added in Windows Server 2012 R2.

Remarks

If the virtual hard disk is a differencing disk, the entire virtual disk chain is opened. If the link is broken in the disk chain, a job object is returned with the appropriate error initialized and the child and parent properties are initialized to the location where the link is broken.

Access to the Msvm_ImageManagementService class might be restricted by UAC Filtering. For more information, see User Account Control and WMI.

Examples

The following C# example validates a virtual hard disk image. The referenced utilities can be found in Common Utilities for the Virtualization Samples.

using System;
using System.Management;

namespace HyperVSamples
{
    class ValidateVHD
    {
        static void ValidateVirtualHardDisk(string vhdPath)
        {
            ManagementScope scope = new ManagementScope(@"root\virtualization", null);
            ManagementObject imageService = Utility.GetServiceObject(scope, "Msvm_ImageManagementService");

            ManagementBaseObject inParams = imageService.GetMethodParameters("ValidateVirtualHardDisk");
            inParams["Path"] = vhdPath;
            ManagementBaseObject outParams = imageService.InvokeMethod("ValidateVirtualHardDisk", inParams, null);
            if ((UInt32)outParams["ReturnValue"] == ReturnCode.Started)
            {
                if (Utility.JobCompleted(outParams, scope))
                {
                    Console.WriteLine("{0} is a valid virtual hard disk.", inParams["Path"]);
                }
                else
                {
                    Console.WriteLine("Unable to validate {0}", inParams["Path"]);
                }
            }

            inParams.Dispose();
            outParams.Dispose();
            imageService.Dispose();
        }

        static void Main(string[] args)
        {
            if (args != null && args.Length != 1)
            {
                Console.WriteLine("Usage: ValidateVHD vhdPath");
                return;
            }
            ValidateVirtualHardDisk(args[0]);
        }

    }
}

The following VBScript example validates a virtual hard disk image.

option explicit 

dim objWMIService
dim managementService
dim fileSystem
dim vhdPath

const JobStarting = 3
const JobRunning = 4
const JobCompleted = 7
const wmiStarted = 4096


Main()

'-----------------------------------------------------------------
' Main
'-----------------------------------------------------------------
Sub Main()
    set fileSystem = Wscript.CreateObject("Scripting.FileSystemObject")
    dim computer, objArgs
    
    computer = "."
    set objWMIService = GetObject("winmgmts:\\" & computer & "\root\virtualization")
    set managementService = objWMIService.ExecQuery("Select * from Msvm_ImageManagementService").ItemIndex(0)


    set objArgs = WScript.Arguments
    if WScript.Arguments.Count = 1 then
        vhdPath = objArgs.Unnamed.Item(0)
    else
        WScript.Echo "usage: cscript ValidateVHD.vbs path"
        WScript.Quit(1)
    end if

    if ValidateVHD(vhdPath) then
        WriteLog "Done"
        WScript.Quit(0)
    else
        WriteLog "ValidateVHD failed"
        WScript.Quit(1)
    end if


End Sub

'-----------------------------------------------------------------
' Execute ValidateVirtualHardDisk
'-----------------------------------------------------------------
Function ValidateVHD(vhdPath)
    WriteLog Format1("Function ValidateVHD({0})",  vhdPath)
    dim objInParam, objOutParams

    ValidateVHD = false

    set objInParam = managementService.Methods_("ValidateVirtualHardDisk").InParameters.SpawnInstance_()
    objInParam.Path = vhdPath

    set objOutParams = managementService.ExecMethod_("ValidateVirtualHardDisk", objInParam)

    if (WMIMethodStarted(objOutParams)) then
        if (WMIJobCompleted(objOutParams)) then
            WriteLog Format1("{0} is a valid virtual hard disk.", vhdPath)
            ValidateVHD = true
        end if
    end if

End Function


'-----------------------------------------------------------------
' Handle wmi return values
'-----------------------------------------------------------------
Function WMIMethodStarted(outParam)
    WriteLog "Function WMIMethodStarted"
    
    dim wmiStatus
    
    WMIMethodStarted = false

    if Not IsNull(outParam) then
        wmiStatus = outParam.ReturnValue

        if  wmiStatus = wmiStarted then
            WMIMethodStarted = true
        else
            WriteLog Format1("Unable to validate {0}", vhdPath)
        end if
   end if

End Function

'-----------------------------------------------------------------
' Handle wmi Job object
'-----------------------------------------------------------------
Function WMIJobCompleted(outParam)
    WriteLog "Function WMIJobCompleted"
    dim WMIJob, jobState

    set WMIJob = objWMIService.Get(outParam.Job)

    WMIJobCompleted = true

    jobState = WMIJob.JobState

    while jobState = JobRunning or jobState = JobStarting
        WriteLog Format1("In progress... {0}% completed.",WMIJob.PercentComplete)
        WScript.Sleep(1000)
        set WMIJob = objWMIService.Get(outParam.Job)
        jobState = WMIJob.JobState
    wend

    if (jobState <> JobCompleted) then
        WriteLog Format1("ErrorCode:{0}", WMIJob.ErrorCode)
        WriteLog Format1("ErrorDescription:{0}", WMIJob.ErrorDescription)
        WMIJobCompleted = false
    end if

End Function

'-----------------------------------------------------------------
' Create the console log files.
'-----------------------------------------------------------------
Sub WriteLog(line)
    dim fileStream
    set fileStream = fileSystem.OpenTextFile(".\ValidateVHD.log", 8, true)
    WScript.Echo line
    fileStream.WriteLine line
    fileStream.Close

End Sub


'------------------------------------------------------------------------------
' The string formatting functions to avoid string concatenation.
'------------------------------------------------------------------------------
Function Format1(myString, arg0)
    Format1 = Replace(myString, "{0}", arg0)
End Function

Requirements

Minimum supported client
None supported
Minimum supported server
Windows Server 2008
End of client support
None supported
End of server support
Windows Server 2012
Namespace
Root\Virtualization
MOF
WindowsVirtualization.mof

See also

ValidateVirtualHardDisk (V2)

CIM_ConcreteJob

Msvm_ImageManagementService