Hyper-V WMI: What VHD’s/Physical Disks Are Associated With a Virtual Machine?

Taylor Brown [Microsoft Hyper-V]

21 Aug 2008 10:10 PM

Comments 6

I got a great question based on yesterday’s post (by the way my e-mail was blocking a lot of external messages that’s fixed now so I apologize to anyone I missed a mail from). The person was asking how they could figure out what physical disk a virtual machine is using when configured for passthough on the host… Well here’s the magic – I took it a little further and got the path’s for any attached VHD’s… Enjoy!

$HyperVParent = "localhost"
$HyperVGuest = "My Virtual Machine"

$VMManagementService = Get-WmiObject -class "Msvm_VirtualSystemManagementService" -namespace "root\virtualization" -ComputerName $HyperVParent
$Vm = Get-WmiObject -Namespace "root\virtualization" -ComputerName $HyperVParent -Query "Select * From Msvm_ComputerSystem Where ElementName='$HyperVGuest'"
$VMSettingData = Get-WmiObject -Namespace "root\virtualization" -Query "Associators of {$Vm} Where ResultClass=Msvm_VirtualSystemSettingData AssocClass=Msvm_SettingsDefineState" -ComputerName $HyperVParent

#
#Getting the Path's for Attached VHD's
$VirtualDiskResource = Get-WmiObject -Namespace "root\virtualization" `
    -Query "Associators of {$VMSettingData} Where ResultClass=Msvm_ResourceAllocationSettingData AssocClass=Msvm_VirtualSystemSettingDataComponent" `
    -ComputerName $HyperVParent | Where-Object { $_.ResourceSubType -match "Microsoft Virtual Hard Disk" }

ForEach-Object -InputObject $VirtualDiskResource -Process {
    Write-Host "Virtual Hard Disk At: $_.Connection[0]"
}

#
#Getting the Disk Attachments for Passthrough Disks
$PhysicalDiskResource = Get-WmiObject -Namespace "root\virtualization" `
    -Query "Associators of {$VMSettingData} Where ResultClass=Msvm_ResourceAllocationSettingData AssocClass=Msvm_VirtualSystemSettingDataComponent" `
    -ComputerName $HyperVParent | Where-Object { $_.ResourceSubType -match "Microsoft Physical Disk Drive" }

ForEach-Object -InputObject $PhysicalDiskResource -Process {
    Write-Host "Passthrough Disk At: " ([WMI]$_.HostResource[0]).ElementName
    Write-Host "Passthrough Disk Drive Number: " ([WMI]$_.HostResource[0]).DriveNumber
}

Taylor Brown
Hyper-V Integration Test Lead
http://blogs.msdn.com/taylorb

Powershell, WMI, Hyper-V - Windows Server 2008