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Enumerating parent KVP data

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As I mentioned on Tuesday, when you send data to a virtual machine using KVPs they are then stored in a collection on the parent side to be pushed into the virtual machine whenever it starts up.  After sending a KVP you can then enumerate the KVPs to see what data is being sent into the virtual machine.

Note that what you are doing here is listing the KVPs that are stored on the parent - not what is currently in the virtual machine (KVPs may have been deleted in the virtual machine, or if the virtual machine has not been started yet they may not have been pushed in).

VBScript:

 Option Explicit

  

 Dim HyperVServer

 Dim VMName

 Dim WMIService

 Dim VM

 Dim KVP

 Dim KVPSettingData

 Dim xmlDoc

 Dim DisplayString

 Dim exchangeDataItem 

 Dim xpath

 Dim node

  

 'Prompt for the Hyper-V Server to use

 HyperVServer = InputBox("Specify the Hyper-V Server to use:") 

  

 'Get name for the virtual machine

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

  

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

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

  

 'Get the VM object that we want

 Set VM = (WMIService.ExecQuery("SELECT * FROM Msvm_ComputerSystem WHERE ElementName='" & VMName & "'")).ItemIndex(0)

  

 'Get the KVP Object for the virtual machine

 Set KVP = (VM.Associators_("Msvm_SystemDevice", "Msvm_KvpExchangeComponent")).ItemIndex(0) 

 Set KVPSettingData = (KVP.Associators_("Msvm_ElementSettingData", "Msvm_KvpExchangeComponentSettingData")).ItemIndex(0) 

  

 'Create an XML object to parse the data

 Set xmlDoc = CreateObject("Microsoft.XMLDOM")

 xmlDoc.async = "false"

  

 'Iterate over HostExchangeItems

 for each exchangeDataItem in KVPSettingData.HostExchangeItems

  

    'Load single exchange data item

    xmlDoc.loadXML(exchangeDataItem) 

  

    'Get the value for node name

    xpath = "/INSTANCE/PROPERTY[@NAME='Name']/VALUE/child:text()"

    set node = xmlDoc.selectSingleNode(xpath)

    DisplayString = DisplayString & node.Text & " : "

  

    'Get the data associated with the VM

    xpath = "/INSTANCE/PROPERTY[@NAME='Data']/VALUE/child:text()"

    set node = xmlDoc.selectSingleNode(xpath)

    DisplayString = DisplayString & node.Text & chr(13)

  

 next

  

 wscript.echo "Parent OS KVPs for " & VMName & chr(10) & chr(10) & DisplayString

PowerShell:

 # Filter for parsing XML data

 filter Import-CimXml 

 { 

    # Create new XML object from input

    $CimXml = [Xml]$_ 

    $CimObj = New-Object -TypeName System.Object 

  

    # Iterate over the data and pull out just the value name and data for each entry

    foreach ($CimProperty in $CimXml.SelectNodes("/INSTANCE/PROPERTY[@NAME='Name']")) 

       { 

          $CimObj | Add-Member -MemberType NoteProperty -Name $CimProperty.NAME -Value $CimProperty.VALUE 

       } 

  

    foreach ($CimProperty in $CimXml.SelectNodes("/INSTANCE/PROPERTY[@NAME='Data']")) 

       { 

          $CimObj | Add-Member -MemberType NoteProperty -Name $CimProperty.NAME -Value $CimProperty.VALUE 

       } 

  

    # Display output

    $CimObj 

 } 

  

 # Prompt for the Hyper-V Server to use

 $HyperVServer = Read-Host "Specify the Hyper-V Server to use (enter '.' for the local computer)"

  

 # Prompt for the virtual machine to use

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

  

 # Get the virtual machine object

 $query = "Select * From Msvm_ComputerSystem Where ElementName='" + $VMName + "'"

 $Vm = gwmi -namespace root\virtualization -query $query -computername $HyperVServer

  

 # Get the KVP Object

 $query = "Associators of {$Vm} Where AssocClass=Msvm_SystemDevice ResultClass=Msvm_KvpExchangeComponent"

 $Kvp = gwmi -namespace root\virtualization -query $query -computername $HyperVServer

  

 $query = "Associators of {$Kvp} Where AssocClass=Msvm_ElementSettingData ResultClass=Msvm_KvpExchangeComponentSettingData"

 $KvpSettingData = gwmi -namespace root\virtualization -query $query -computername $HyperVServer

  

 Write-Host

 Write-Host "Parent KVP information for" $VMName

  

 # Filter the results

 $KvpSettingData.HostExchangeItems | Import-CimXml

Cheers,

Ben