CreateDifferencingVirtualHardDisk method of the Msvm_ImageManagementService class
Creates a differencing virtual hard disk (.vhd) file.
Syntax
uint32 CreateDifferencingVirtualHardDisk(
[in] string Path,
[in] string ParentPath,
[out] CIM_ConcreteJob REF Job
);
Parameters
-
Path [in]
-
Type: string
A fully qualified path that specifies the location of the new file.
-
ParentPath [in]
-
Type: string
A fully qualified path that specifies the location of the parent virtual hard disk file.
-
Job [out]
-
Type: CIM_ConcreteJob
A reference to the job (can be null if the task is completed).
Return value
Type: uint32
This method can return one of the following values.
-
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)
Remarks
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 creates a differencing virtual hard disk file. The referenced utilities can be found in Common Utilities for the Virtualization Samples.
using System;
using System.Management;
namespace HyperVSamples
{
class CreateDiffVHD
{
static void CreateDifferencingVirtualHardDisk(string path, string parentPath)
{
ManagementScope scope = new ManagementScope(@"root\virtualization", null);
ManagementObject imageService = Utility.GetServiceObject(scope, "Msvm_ImageManagementService");
ManagementBaseObject inParams = imageService.GetMethodParameters("CreateDifferencingVirtualHardDisk");
inParams["ParentPath"] = parentPath;
inParams["Path"] = path;
ManagementBaseObject outParams = imageService.InvokeMethod("CreateDifferencingVirtualHardDisk", inParams, null);
if ((UInt32)outParams["ReturnValue"] == ReturnCode.Started)
{
if (Utility.JobCompleted(outParams, scope))
{
Console.WriteLine("{0} was created successfully.", inParams["Path"]);
}
else
{
Console.WriteLine("Unable to create {0}", inParams["Path"]);
}
}
inParams.Dispose();
outParams.Dispose();
imageService.Dispose();
}
static void Main(string[] args)
{
if (args != null && args.Length != 2)
{
Console.WriteLine("Usage: CreateDiffVHD path, parentPath");
return;
}
CreateDifferencingVirtualHardDisk(args[0], args[1]);
}
}
}
The following VBScript example creates a differencing virtual hard disk file.
option explicit
dim objWMIService
dim computerName
dim managementService
dim fileSystem
const JobStarting = 3
const JobRunning = 4
const JobCompleted = 7
const wmiStarted = 4096
const method = "CreateDifferencingVirtualHardDisk"
Main()
'-----------------------------------------------------------------
' Main routine
'-----------------------------------------------------------------
Sub Main()
dim path, parentPath, computer, objArgs
set fileSystem = Wscript.CreateObject("Scripting.FileSystemObject")
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 = 2 then
path = objArgs.Unnamed.Item(0)
parentPath = objArgs.Unnamed.Item(1)
else
WScript.Echo "usage: cscript CreateDiffVHD.vbs path ParentPath"
WScript.Quit(1)
end if
if ExecuteCreateDiffVHD(path, parentPath) then
WriteLog "Done"
WScript.Quit(0)
else
WriteLog "CreateDiffVHD failed"
WScript.Quit(1)
end if
End Sub
'-----------------------------------------------------------------
' Execute CreateDifferencingVirtualHardDisk
'-----------------------------------------------------------------
Function ExecuteCreateDiffVHD(path, parentPath)
WriteLog Format2("Sub ExecuteCreateDiffVHD({0}, {1})", Path, ParentPath)
dim objInParam, objOutParams
ExecuteCreateDiffVHD = false
set objInParam = managementService.Methods_("CreateDifferencingVirtualHardDisk").InParameters.SpawnInstance_()
objInParam.Path = path
objInParam.ParentPath = parentPath
set objOutParams = managementService.ExecMethod_("CreateDifferencingVirtualHardDisk", objInParam)
if (WMIMethodStarted(objOutParams)) then
if (WMIJobCompleted(objOutParams)) then
WriteLog Format2("'{0}' was created as a differencing disk of '{1}' .", Path, ParentPath)
ExecuteCreateDiffVHD = 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 Format3("Failed to create differencing disk {0} for {1} with error {2}", Path, ParentPath, wmiStatus)
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(".\CreateDiffVHD.log", 8, true)
WScript.Echo line
fileStream.WriteLine line
fileStream.Close
End Sub
'------------------------------------------------------------------------------
' The string formatting functions to avoid string concatenation.
'------------------------------------------------------------------------------
Function Format3(myString, arg0, arg1, arg2)
Format3 = Format2(myString, arg0, arg1)
Format3 = Replace(Format3, "{2}", arg2)
End Function
'------------------------------------------------------------------------------
' The string formatting functions to avoid string concatenation.
'------------------------------------------------------------------------------
Function Format2(myString, arg0, arg1)
Format2 = Format1(myString, arg0)
Format2 = Replace(Format2, "{1}", arg1)
End Function
'------------------------------------------------------------------------------
' 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 |
|