How Are My VHD’s/Passthough Disk’s Connected To My Virtual Machine?

Updated 2/23 – Added VHD File Size and Fixed a Few Bugs.

This is a follow up on my previous post on Hyper-V WMI: What VHD’s/Physical Disks Are Associated With a Virtual Machine?.  I had been getting questions about how to better identify what disks are connected to what bus location/controller.  Specifically I have been getting a lot of questions about how back up or copy just the VHD that the guest sees as drive letter C or D etc… I wrote a revised script that gives a bit more information specifically the controller addresses and the Instance ID of the controller.  The reason that’s interesting is that you can determine that the C volume is on Disk Number 1 and that Disk Number 1 is connected to IDE Port 0/1 and on the parent you know that IDE Port 0/1 is backed by S:\vhds\foo.vhd well then you know what to backup…  So what about SCSI controller’s?  Well they are a bit more challenging but not to much – if you look at the PNP ID of the controller its VMBUS\<GUID> where the GUID is the same as the first GUID in the WMI instance id for the controller on the management OS (take a look at the screen capture below).  Hopefully this is helpful – Enjoy!

Here’s the Script:

$HyperVParent = "localhost" $VMManagementService = Get-WmiObject -class "Msvm_VirtualSystemManagementService" -namespace "root\virtualization" -ComputerName $HyperVParent foreach ($vm in Get-WmiObject -Namespace root\virtualization -Query "Select * From Msvm_ComputerSystem where Description='Microsoft Virtual Machine'" -ComputerName $HyperVParent){     $VMSettingData = Get-WmiObject -Namespace "root\virtualization" -Query "Associators of {$Vm} Where ResultClass=Msvm_VirtualSystemSettingData AssocClass=Msvm_SettingsDefineState" -ComputerName $HyperVParent      $VirtualDiskResource = Get-WmiObject -Namespace "root\virtualization" `        -Query "Associators of {$VMSettingData} Where ResultClass=Msvm_ResourceAllocationSettingData AssocClass=Msvm_VirtualSystemSettingDataComponent" `        -ComputerName $HyperVParent | Where-Object { $_.ResourceSubType -match "Microsoft Virtual Hard Disk" }     $PhysicalDiskResource = Get-WmiObject -Namespace "root\virtualization" `        -Query "Associators of {$VMSettingData} Where ResultClass=Msvm_ResourceAllocationSettingData AssocClass=Msvm_VirtualSystemSettingDataComponent" `        -ComputerName $HyperVParent | Where-Object { $_.ResourceSubType -match "Microsoft Physical Disk Drive" }     if ($VirtualDiskResource -ne $null) {        Write-Host "VHD Connections: "        foreach ($i in $VirtualDiskResource) {            Write-Host " Virtual Hard Disk At: " ([WMI]$i).Connection[0]            Write-Host " Virtual Hard Disk VHD Size: " (get-item ([WMI]$i).Connection[0]).Length            Write-Host " Virtual Hard Disk Connected To: " ([WMI]([WMI]$i.Parent).Parent).ElementName            Write-Host " Controller Index: " ([WMI]([WMI]$i.Parent).Parent).Address            Write-Host " Controller Instance ID: " ([WMI]([WMI]$i.Parent).Parent).InstanceID            Write-Host " Disk Location On Controller: " ([WMI]$i.Parent).Address            Write-Host     } }     if ($PhysicalDiskResource -ne $null) {        Write-Host "Physical Disk Connections: "        foreach ($i in $PhysicalDiskResource) {            Write-Host " Passthrough Disk At:" ([WMI]$i.HostResource[0]).ElementName            Write-Host " Passthrough Disk Drive Number: " ([WMI]$i.HostResource[0]).DriveNumber            Write-Host " Virtual Hard Disk Connected To: " ([WMI]$i.Parent).ElementName            Write-Host " Controller Index: " ([WMI]$i.Parent).Address            Write-Host " Controller Instance ID: " ([WMI]$i.Parent).InstanceID            Write-Host " Disk Location On Controller: " ([WMI]$i).Address            Write-Host } }}

 

Here’s the Output of the Script:

PS D:\> .\DiskAttachment2.ps1 VHD Connections: Virtual Hard Disk At: C:\Users\Public\Documents\Hyper-V\Virtual hard disks\SERVER2008-ENT-64-6001.18000.080118-1840_amd64fre_ServerEnterprise_en-us_VL.vhd Virtual Hard Disk Connected To: IDE Controller 0 Controller Index: 0 Controller Instance ID: Microsoft:4DA5F246-7501-49B3-AE41-B1B5B4FCF57F\83F8638B-8DCA-4152-9EDA-2CA8B33039B4\0 Disk Location On Controller: 0 Virtual Hard Disk At: C:\vhd\VHD on Local Storage.vhd Virtual Hard Disk Connected To: IDE Controller 0 Controller Index: 0 Controller Instance ID: Microsoft:4DA5F246-7501-49B3-AE41-B1B5B4FCF57F\83F8638B-8DCA-4152-9EDA-2CA8B33039B4\0 Disk Location On Controller: 1 Virtual Hard Disk At: S:\Vhds\VHD on LUN.vhd Virtual Hard Disk Connected To: SCSI Controller Controller Index: Controller Instance ID: Microsoft:4DA5F246-7501-49B3-AE41-B1B5B4FCF57F\B090A115-B8E6-4706-BE6C-C8ECDDC4A90B\0 Disk Location On Controller: 1 Virtual Hard Disk At: S:\Vhds\Disk on SCSI 2.vhd Virtual Hard Disk Connected To: SCSI Controller Controller Index: Controller Instance ID: Microsoft:4DA5F246-7501-49B3-AE41-B1B5B4FCF57F\87617569-E20C-4982-AC44-04A4251C82BA\0 Disk Location On Controller: 0 Physical Disk Connections: Passthrough Disk At: Disk 3 Passthrough Disk Drive Number: 3 Virtual Hard Disk Connected To: SCSI Controller Controller Index: Controller Instance ID: Microsoft:4DA5F246-7501-49B3-AE41-B1B5B4FCF57F\B090A115-B8E6-4706-BE6C-C8ECDDC4A90B\0 Disk Location On Controller: 0

 

Here’s a Screen Capture Of the PNP ID in the Guest:

Taylor Brown

Hyper-V Integration Test Lead

https://blogs.msdn.com/taylorb

Comments

• Anonymous
  February 23, 2009
  PingBack from http://www.ditii.com/2009/02/24/how-are-my-vhd%e2%80%99spassthough-disk%e2%80%99s-connected-to-my-virtual-machine/

• Anonymous
  December 05, 2009
  <quote> if you look at the PNP ID of the controller its VMBUS<GUID> where the GUID is the same as the first GUID in the WMI instance id for the controller on the management OS </quote> I don't find any similar GUID in the screen shot? Any further calculation needed?

• Anonymous
  January 22, 2010
  The comment has been removed

• Anonymous
  November 22, 2010
  I don't see the match for the SCSI controllers guids in your sample. Am I missing something?