RemoveVirtualSystemSnapshotTree method of the Msvm_VirtualSystemManagementService class

Removes an existing snapshot and all its children of a virtual system.

Syntax

uint32 RemoveVirtualSystemSnapshotTree(
  [in]  CIM_VirtualSystemSettingData REF SnapshotSettingData,
  [out] CIM_ConcreteJob              REF Job
);

Parameters

SnapshotSettingData [in]

Type: CIM_VirtualSystemSettingData

A reference to the CIM_VirtualSystemSettingData instance which represents the snapshot tree to be removed.

Job [out]

Type: CIM_ConcreteJob

An optional parameter for monitoring progress of the operation, which is used if the method could not be executed synchronously. If the operation is executing asynchronously, the return value is 4096.

Return value

Type: uint32

This method returns 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 use (32774)

Invalid state for this operation (32775)

Incorrect data type (32776)

System is not available (32777)

Out of memory (32778)

Remarks

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

Examples

The following C# sample removes a snapshot tree from a virtual system. The referenced utilities can be found in Common Utilities for the Virtualization Samples.

[!Important]
To function correctly, the following code must be run on the VM host server, and must be run with Administrator privileges.

using System;
using System.Management;

namespace HyperVSamples
{
    class RemoveVirtualSystemSnapshotTreeClass
    {
        static ManagementObject GetLastAppliedVirtualSystemSnapshot(ManagementObject vm)
        {
            ManagementObjectCollection settings = vm.GetRelated(
                "Msvm_VirtualSystemsettingData",
                "Msvm_LastAppliedSettingData ",
                null,
                null,
                "SettingData",
                "ManagedElement",
                false,
                null);

            ManagementObject virtualSystemsetting = null;
            foreach (ManagementObject setting in settings)
            {
                Console.WriteLine(setting.Path.Path);
                Console.WriteLine(setting["ElementName"]);
                virtualSystemsetting = setting;

            }

            return virtualSystemsetting;
        }

        static void RemoveVirtualSystemSnapshotTree(string vmName)
        {
            ManagementScope scope = new ManagementScope(@"root\virtualization", null);

            ManagementObject virtualSystemService = Utility.GetServiceObject(scope, "Msvm_VirtualSystemManagementService");

            ManagementBaseObject inParams = virtualSystemService.GetMethodParameters("RemoveVirtualSystemSnapshotTree");

            ManagementObject vm = Utility.GetTargetComputer(vmName, scope);

            ManagementObject vmSnapshot = GetLastAppliedVirtualSystemSnapshot(vm);

            inParams["SnapshotsettingData"] = vmSnapshot.Path.Path;

            ManagementBaseObject outParams = virtualSystemService.InvokeMethod("RemoveVirtualSystemSnapshotTree", inParams, null);

            if ((UInt32)outParams["ReturnValue"] == ReturnCode.Started)
            {
                if (Utility.JobCompleted(outParams, scope))
                {
                    Console.WriteLine("Snapshot tree was removed successfully.");

                }
                else
                {
                    Console.WriteLine("Failed to remove snapshot tree");
                }
            }
            else if ((UInt32)outParams["ReturnValue"] == ReturnCode.Completed)
            {
                Console.WriteLine(outParams["SnapshotsettingData"].ToString());
                Console.WriteLine("Snapshot tree was removed successfully.");
            }
            else
            {
                Console.WriteLine("Remove virtual system snapshot tree failed with error {0}", outParams["ReturnValue"]);
            }

            inParams.Dispose();
            outParams.Dispose();
            vm.Dispose();
            vmSnapshot.Dispose();
            virtualSystemService.Dispose();
        }

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

The following VBScript sample removes a snapshot tree from a virtual system.

[!Important]
To function correctly, the following code must be run on the VM host server, and must be run with Administrator privileges.

option explicit 

dim objWMIService
dim managementService
dim fileSystem

const JobStarting = 3
const JobRunning = 4
const JobCompleted = 7
const wmiStarted = 4096
const wmiSuccessful = 0


Main()

'-----------------------------------------------------------------
' Main
'-----------------------------------------------------------------
Sub Main()
    dim computer, objArgs, vmName, vm, snapshotSetting
    
    set fileSystem = Wscript.CreateObject("Scripting.FileSystemObject")
    computer = "."
    set objWMIService = GetObject("winmgmts:\\" & computer & "\root\virtualization")
    set managementService = objWMIService.ExecQuery("select * from Msvm_VirtualSystemManagementService").ItemIndex(0)
    
    set objArgs = WScript.Arguments
    if WScript.Arguments.Count = 1 then
        vmName = objArgs.Unnamed.Item(0)
    else
        WScript.Echo "usage: cscript RemoveVirtualSystemSnapshottree.vbs vmName"
        WScript.Quit(1)
    end if
 
    set vm = GetComputerSystem(vmName)
    set snapshotSetting = GetComputerSystemSnapshotSettings(vm)

    if RemoveVirtualSystemSnapshottree(snapshotSetting) then
        WriteLog "Done"
        WScript.Quit(0)
    else
        WriteLog "RemoveVirtualSystemSnapshotTree failed."
        WScript.Quit(1)
    end if
End Sub

'-----------------------------------------------------------------
' Retrieve Msvm_VirtualComputerSystem from base on its ElementName
'-----------------------------------------------------------------
Function GetComputerSystem(vmElementName)
    On Error Resume Next
    dim query
    query = Format1("select * from Msvm_ComputerSystem where ElementName = '{0}'", vmElementName)
    set GetComputerSystem = objWMIService.ExecQuery(query).ItemIndex(0)
    if (Err.Number <> 0) then
        WriteLog Format1("Err.Number: {0}", Err.Number)
        WriteLog Format1("Err.Description:{0}",Err.Description)
        WScript.Quit(1)
    end if
End Function

'-----------------------------------------------------------------
' Retrieve the last applied Msvm_VirtualComputerSystem snapshot
'-----------------------------------------------------------------
Function GetComputerSystemSnapshotSettings(computerSystem)
    On Error Resume Next
    dim query
    query = Format1("ASSOCIATORS OF {{0}} WHERE resultClass = Msvm_VirtualSystemsettingData AssocClass = Msvm_LastAppliedSettingData", computerSystem.Path_.Path)
    set GetComputerSystemSnapshotSettings = objWMIService.ExecQuery(query).ItemIndex(0)
    if (Err.Number <> 0) then
        WriteLog Format1("Err.Number: {0}", Err.Number)
        WriteLog Format1("Err.Description:{0}",Err.Description)
        WScript.Quit(1)
    end if
End Function

'-----------------------------------------------------------------
' Remove a virtual system Snapshot
'-----------------------------------------------------------------
Function RemoveVirtualSystemSnapshottree(snapshotSettingData)

    dim objInParam, objOutParams
    
    RemoveVirtualSystemSnapshottree = false
    set objInParam = managementService.Methods_("RemoveVirtualSystemSnapshottree").InParameters.SpawnInstance_()
    objInParam.SnapshotSettingData = snapshotSettingData.Path_.Path
    
    set objOutParams = managementService.ExecMethod_("RemoveVirtualSystemSnapshottree", objInParam)

    if objOutParams.ReturnValue = wmiStarted then
        if (WMIJobCompleted(objOutParams)) then
            RemoveVirtualSystemSnapshottree = true
        end if
    elseif objOutParams.ReturnValue = wmiSuccessful then
        RemoveVirtualSystemSnapshottree = true
    else
        WriteLog Format1("RemoveVirtualSystemSnapshotTree failed with ReturnValue {0}", objOutParams.ReturnValue)
    end if

End Function

'-----------------------------------------------------------------
' Handle wmi Job object
'-----------------------------------------------------------------
Function WMIJobCompleted(outParam)

    dim WMIJob, jobState
    WMIJobCompleted = true

    set WMIJob = objWMIService.Get(outParam.Job)
    
    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 (WMIJob.JobState <> JobCompleted) then
        WriteLog Format1("ErrorDescription:{0}", WMIJob.ErrorDescription)
        WriteLog Format1("ErrorCode:{0}", WMIJob.ErrorCode)
        WMIJobCompleted = false
    end if

End Function

'-----------------------------------------------------------------
' Create the console log files.
'-----------------------------------------------------------------
Sub WriteLog(line)
    dim fileStream
    set fileStream = fileSystem.OpenTextFile(".\RemoveVirtualSystemSnapshotTree.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

Msvm_VirtualSystemManagementService

CIM_VirtualSystemSettingData

CIM_ConcreteJob

DestroySnapshotTree (V2)