# Hyper-V on Windows Server 2025: nested lab, VM switch and licensing

> Enable the Hyper-V role on a Windows Server 2025 lab VM, create a NAT/external switch and a generation-2 VM, and keep the Standard/Datacenter licensing boundary visible.

**Tested on**

- Build: 26100.33650
- Edition: Standard / Datacenter
- Architecture: x64
- Evidence: E1
- Verified: 2026-10-28

## The short answer

Hyper-V on Server 2025 is the same role, with the licensing boundary you already met:

- **Standard:** two OSEs on the licensed host (host only virtualises), or one if the host also runs roles.
- **Datacenter:** unlimited OSEs on the licensed host, plus S2D/Storage Replica.
- A **nested** Hyper-V VM on PVE needs CPU virtualization exposed (`host` CPU, nested enabled).

Do not enable Hyper-V on the PVE Windows guest and assume it will work without nested virtualization.

## Prerequisites

| Check | Why |
|---|---|
| PVE CPU type `host` | Exposes VT-x/AMD-V |
| Nested virtualization enabled | Outer hypervisor must allow it |
| 8GB+ RAM | Host + guest VMs |
| Separate virtual disk | VM storage |
| Static IP / external switch | Management and guest networking |

```powershell
systeminfo | Select-String 'Hyper-V'
Get-WindowsFeature Hyper-V
```

## Install

```powershell
Install-WindowsFeature Hyper-V -IncludeManagementTools
Restart-Computer
```

After reboot, use Hyper-V Manager or PowerShell. Create a **generation 2** VM for UEFI/Secure Boot; generation 1 only for legacy guests.

## Virtual switch

| Type | Use | Caveat |
|---|---|---|
| External | VM on the physical LAN | Binds the host NIC; plan management access |
| Internal | Host ↔ VMs only | No LAN access without NAT/routing |
| Private | VM ↔ VM only | No host access |

For a lab behind PVE, an **internal** switch plus NAT is often safer than an external switch that exposes the nested VM to the home LAN.

```powershell
New-VMSwitch -Name 'LabNat' -SwitchType Internal
Get-NetAdapter
New-NetIPAddress -InterfaceAlias 'vEthernet (LabNat)' -IPAddress 192.168.50.1 -PrefixLength 24
New-NetNat -Name 'LabNat' -InternalIPInterfaceAddressPrefix 192.168.50.0/24
```

## Create a VM

```powershell
New-VM -Name 'lab-client' -MemoryStartupBytes 4GB -Generation 2 -NewVHDPath 'D:\VMs\lab-client.vhdx' -NewVHDSizeBytes 60GB -SwitchName 'LabNat'
Set-VMProcessor -VMName 'lab-client' -Count 2
Start-VM -Name 'lab-client'
```

Attach an ISO, install the guest, then verify:

```powershell
Get-VM
Get-VMSwitch
Get-VMNetworkAdapter -VMName 'lab-client'
```

> **Caution: Licensing follows the host, not the VM count**
>
> A lab evaluation is still an evaluation. Do not use Hyper-V to multiply unlicensed Windows Server instances. Check the Standard/Datacenter OSE count before you build a farm.

## Nested limits

- Nested guests are slower and may lack some hardware features.
- Dynamic memory/checkpoints work, but do not treat a nested lab as a performance benchmark.
- Anti-cheat/DRM in a nested VM is not a supported configuration.
- Snapshot the outer PVE VM before enabling Hyper-V; rollback is cheaper than repairing a broken nested stack.

## Sources

- [Microsoft Learn — Hyper-V overview](https://learn.microsoft.com/en-us/windows-server/virtualization/hyper-v/hyper-v-technology-overview)
- [Microsoft Learn — Hyper-V VM switch](https://learn.microsoft.com/en-us/windows-server/virtualization/hyper-v/get-started/create-a-virtual-switch-for-hyper-v-virtual-machines)

---

Source: https://windows.homes/en/server/roles/hyper-v/