./Enable-NestedVM.ps1
param([string]$vmName)
# Enable-NestedVm.ps1
# Checks VM for nesting comatability and configures if not properly setup.
# Author: Drew Cross
if([string]::IsNullOrEmpty($vmName)) {
Write-Host «No VM name passed»
Exit;
}
# Constants
$4GB = 4294967296
# Need to run elevated. Do that here.
# Get the ID and security principal of the current user account
$myWindowsID = [System.Security.Principal.WindowsIdentity]::GetCurrent();
$myWindowsPrincipal=New-Object System.Security.Principal.WindowsPrincipal($myWindowsID);
# Get the security principal for the administrator role
$adminRole = [System.Security.Principal.WindowsBuiltInRole]::Administrator;
# Check to see if we are currently running as an administrator
if ($myWindowsPrincipal.IsInRole($adminRole)) {
# We are running as an administrator, so change the title and background colour to indicate this
$Host.UI.RawUI.WindowTitle = $myInvocation.MyCommand.Definition + «(Elevated)»;
} else {
# We are not running as an administrator, so relaunch as administrator
# Create a new process object that starts PowerShell
$newProcess = New-Object System.Diagnostics.ProcessStartInfo «PowerShell»;
# Specify the current script path and name as a parameter with added scope and support for scripts with spaces in it’s path
$newProcess.Arguments = «& ‘» + $script:MyInvocation.MyCommand.Path + «‘»
# Indicate that the process should be elevated
$newProcess.Verb = «runas»;
# Start the new process
[System.Diagnostics.Process]::Start($newProcess) | Out-Null;
# Exit from the current, unelevated, process
Exit;
}
# Get Vm Information
$vm = Get-VM -Name $vmName
$vmInfo = New-Object PSObject
# VM info
Add-Member -InputObject $vmInfo NoteProperty -Name «ExposeVirtualizationExtensions» -Value $false
Add-Member -InputObject $vmInfo NoteProperty -Name «DynamicMemoryEnabled» -Value $vm.DynamicMemoryEnabled
Add-Member -InputObject $vmInfo NoteProperty -Name «SnapshotEnabled» -Value $false
Add-Member -InputObject $vmInfo NoteProperty -Name «State» -Value $vm.State
Add-Member -InputObject $vmInfo NoteProperty -Name «MacAddressSpoofing» -Value ((Get-VmNetworkAdapter -VmName $vmName).MacAddressSpoofing)
Add-Member -InputObject $vmInfo NoteProperty -Name «MemorySize» -Value (Get-VMMemory -VmName $vmName).Startup
# is nested enabled on this VM?
$vmInfo.ExposeVirtualizationExtensions=(Get-VMProcessor-VM $vm).ExposeVirtualizationExtensions
Write-Host «This script will set the following for $vmName in order to enable nesting:»
$prompt = $false;
# Output text for proposed actions
if ($vmInfo.State -eq ‘Saved’) {
Write-Host «\tSaved state will be removed»
$prompt = $true
}
if ($vmInfo.State -ne ‘Off’ -or $vmInfo.State -eq ‘Saved’) {
Write-Host «Vm State:» $vmInfo.State
Write-Host » $vmName will be turned off»
$prompt = $true
}
if ($vmInfo.ExposeVirtualizationExtensions -eq $false) {
Write-Host » Virtualization extensions will be enabled»
$prompt = $true
}
if ($vmInfo.DynamicMemoryEnabled -eq $true) {
Write-Host » Dynamic memory will be disabled»
$prompt = $true
}
if($vmInfo.MacAddressSpoofing -eq ‘Off’){
Write-Host » Optionally enable mac address spoofing»
$prompt = $true
}
if($vmInfo.MemorySize -lt $4GB) {
Write-Host » Optionally set vm memory to 4GB»
$prompt = $true
}
if(-not $prompt) {
Write-Host » None, vm is already setup for nesting»
Exit;
}
Write-Host «Input Y to accept or N to cancel:» -NoNewline
$char = Read-Host
while(-not ($char.StartsWith(‘Y’) -or $char.StartsWith(‘N’))) {
Write-Host «Invalid Input, Y or N»
$char = Read-Host
}
if($char.StartsWith(‘Y’)) {
if ($vmInfo.State -eq ‘Saved’) {
Remove-VMSavedState -VMName $vmName
}
if ($vmInfo.State -ne ‘Off’ -or $vmInfo.State -eq ‘Saved’) {
Stop-VM -VMName $vmName
}
if ($vmInfo.ExposeVirtualizationExtensions -eq $false) {
Set-VMProcessor -VMName $vmName -ExposeVirtualizationExtensions $true
}
if ($vmInfo.DynamicMemoryEnabled -eq $true) {
Set-VMMemory -VMName $vmName -DynamicMemoryEnabled $false
}
# Optionally turn on mac spoofing
if($vmInfo.MacAddressSpoofing -eq ‘Off’) {
Write-Host «Mac Address Spoofing isn’t enabled (nested guests won’t have network).» -ForegroundColor Yellow
Write-Host «Would you like to enable MAC address spoofing? (Y/N)» -NoNewline
$input = Read-Host
if($input -eq ‘Y’) {
Set-VMNetworkAdapter -VMName $vmName -MacAddressSpoofing on
}
else {
Write-Host «Not enabling Mac address spoofing.»
}
}
if($vmInfo.MemorySize -lt $4GB) {
Write-Host «VM memory is set less than 4GB, without 4GB or more, you may not be able to start VMs.» -ForegroundColor Yellow
Write-Host «Would you like to set Vm memory to 4GB? (Y/N)» -NoNewline
$input = Read-Host
if($input -eq ‘Y’) {
Set-VMMemory -VMName $vmName -StartupBytes $4GB
}
else {
Write-Host «Not setting Vm Memory to 4GB.»
}
}
Exit;
}
if($char.StartsWith(‘N’)) {
Write-Host «Exiting…»
Exit;
}
Write-Host ‘Invalid input’

El script anterior está extraído de la fuente:

https://github.com/MicrosoftDocs/Virtualization-Documentation/blob/master/hyperv-tools/Nested

Ten en cuenta que la Virtualización anidada/nested no se debe utilizar en ningún entorno de producción, solo para pruebas, el rendimiento en general cae bastante.