Scripting VM Creation with Hyper-V

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People have been bugging me for this for a while - so here we go.

Here are the VBScripts / PowerShell scripts to create a basic virtual machine:

VBScript:

 Option Explicit

  

 Dim HyperVServer

 Dim VMName

 Dim WMIService

 Dim VSManagementService

 Dim VSGlobalSettingData

 Dim Result

 Dim Job

 Dim InParam

 Dim OutParam

  

 'Prompt for the Hyper-V Server to use

 HyperVServer = InputBox("Specify the Hyper-V Server to create the virtual machine on:")

  

 'Prompt for the new VM name

 VMName = InputBox("Specify the name for the new virtual machine:")

  

 'Get an instance of the WMI Service in the virtualization namespace.

 Set WMIService = GetObject("winmgmts:\\" & HyperVServer & "\root\virtualization")

  

 'Get the VirtualSystemManagementService object

 Set VSManagementService = WMIService.ExecQuery("SELECT * FROM Msvm_VirtualSystemManagementService").ItemIndex(0)

  

 ' Initialize a new global settings for the VM

 Set VSGlobalSettingData = WMIService.Get("Msvm_VirtualSystemGlobalSettingData").SpawnInstance_()

  

 'Set the VM name

 VSGlobalSettingData.ElementName = VMName

  

 'Setup the input parameter list

 Set InParam = VSManagementService.Methods_("DefineVirtualSystem").InParameters.SpawnInstance_()

 InParam.SystemSettingData = VSGlobalSettingData.GetText_(1) 

  

 'Execute the method and store the results in OutParam

 Set OutParam = VSManagementService.ExecMethod_("DefineVirtualSystem", InParam) 

  

 'Check to see if the job completed synchronously

 if (OutParam.ReturnValue = 0) then

    Wscript.Echo "Virtual machine created."

 elseif (OutParam.ReturnValue <> 4096) then

    Wscript.Echo "Failed to create virtual machine"

 else   

  

    'Get the job object

    set Job = WMIService.Get(OutParam.Job)

  

     'Wait for the job to complete (3 == starting, 4 == running)

    while (Job.JobState = 3) or (Job.JobState = 4)

       Wscript.Echo Job.PercentComplete

       WScript.Sleep(1000)

  

       'Refresh the job object

       set Job = WMIService.Get(OutParam.Job)

    Wend

  

    'Provide details if the job fails (7 == complete)

    if (Job.JobState <> 7) then

       Wscript.Echo "Failed to create virtual machine"

       Wscript.Echo "ErrorCode:" & Job.ErrorCode

       Wscript.Echo "ErrorDescription:" & Job.ErrorDescription

    else

       Wscript.Echo "Virtual machine created."

    end If

 end if

PowerShell:

 # Prompt for the Hyper-V Server to use

 $HyperVServer = Read-Host "Specify the Hyper-V Server to create the virtual machine on"

  

 # Get name for new VM

 $VMName = Read-Host "Specify the name for the new virtual machine"

  

 # Create new MSVM_VirtualSystemGlobalSettingData object

 $wmiClassString = "\\" + $HyperVServer + "\root\virtualization:Msvm_VirtualSystemGlobalSettingData"

 $wmiClass = [WMIClass]$wmiClassString

 $newVSGlobalSettingData = $wmiClass.CreateInstance()

  

 # wait for the new object to be populated

 while ($newVSGlobalSettingData.psbase.Properties -eq $null) {}

  

 # Set the VM name

 $newVSGlobalSettingData.psbase.Properties.Item("ElementName").value = $VMName

  

 # Get the VirtualSystemManagementService object

 $VSManagementService = gwmi MSVM_VirtualSystemManagementService -namespace "root\virtualization" -computername $HyperVServer

  

 # Create the VM

 $result = $VSManagementService.DefineVirtualSystem($newVSGlobalSettingData.psbase.GetText(1))

  

 #Return success if the return value is "0"

 if ($Result.ReturnValue -eq 0)

    {write-host "Virtual machine created."} 

  

 #If the return value is not "0" or "4096" then the operation failed

 ElseIf ($Result.ReturnValue -ne 4096)

    {write-host "Failed to create virtual machine"}

  

   Else

    {#Get the job object

     $job=[WMI]$Result.job

  

     #Provide updates if the jobstate is "3" (starting) or "4" (running)

     while ($job.JobState -eq 3 -or $job.JobState -eq 4)

       {write-host $job.PercentComplete

        start-sleep 1

  

        #Refresh the job object

        $job=[WMI]$Result.job}

  

      #A jobstate of "7" means success

     if ($job.JobState -eq 7)

        {write-host "Virtual machine created."}

       Else

        {write-host "Failed to create virtual machine"

         write-host "ErrorCode:" $job.ErrorCode

         write-host "ErrorDescription" $job.ErrorDescription}

    }

The basic concept here is that you need to create a new instance of Msvm_VirtualSystemGlobalSettingData and then pass it to the DefineVirtualSystem method on the MSVM_VirtualSystemManagementService object.

This will create a new blank virtual machine with no virtual hard disks, network adapters, etc... (I will dig into creating virtual machines with all these bits later).

Note that both of these scripts allow you to specify a remote Hyper-V server to create the virtual machine on.

Cheers,

Ben