# Migrating a Windows Server 2025 VM from VMware ESXi to Proxmox VE

This guide describes the most reliable and direct way to migrate a Windows Server 2025 virtual machine
from **VMware ESXi** to **Proxmox VE**, using `virt-v2v`.  
It also covers driver preparation and alternative manual import steps.

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## 🧭 Overview

| Method | How it works | Pros | Cons |
|--------|---------------|------|------|
| **virt-v2v (recommended)** | Converts directly from ESXi to Proxmox | Keeps partitions, converts drivers | Requires CLI |
| **VMDK import** | Export disk → `qm importdisk` | Simple | Manual driver fix |
| **Veeam restore** | Restore backup | Handy for existing policy | Often fails to boot |

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## ✅ Prerequisites

- Both **ESXi** and **Proxmox VE** hosts reachable on the same network.
- Proxmox host has sufficient storage and CPU.
- Administrative credentials for ESXi (usually `root`).
- `virtio-win.iso` downloaded and stored in `/var/lib/vz/template/iso/`.

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## 🔧 1. Prepare Windows VM on ESXi

Before migrating, pre-install VirtIO drivers inside the Windows VM to ensure it boots in Proxmox.

Run this PowerShell script inside the VM (as Administrator):

```powershell
Set-ExecutionPolicy Bypass -Scope Process -Force
irm https://git.voskuil.cloud/marco/scripts/raw/branch/main/Prep-VirtIODrivers.ps1 | iex
```

This mounts the VirtIO ISO, injects `vioscsi`, `viostor`, `NetKVM`, and `Balloon` drivers,
and makes them available in the Windows driver store.

---

## 🧱 2. Install tools on the Proxmox host

```bash
apt update
apt install virt-v2v libguestfs-tools -y
```

---

## 🚀 3. Run the conversion

Replace the example values with your own host and VM names.

```bash
export LIBGUESTFS_BACKEND=direct

virt-v2v   -ic esx://root@esx01.gpeu.local/?no_verify=1   -o local   -os /var/lib/vz/images/9001   "WIN2025-SRV"
```

- `esx01.gpeu.local` → your ESXi host  
- `WIN2025-SRV` → your VM name on ESXi  
- `9001` → the VMID you plan to use in Proxmox  

This converts the VM’s disks and configuration to a Proxmox-compatible format.

---

## 🖥️ 4. Create and attach the VM in Proxmox

```bash
qm create 9001 --name WIN2025-SRV --memory 8192 --cores 4 --scsihw virtio-scsi-pci
qm importdisk 9001 /var/lib/vz/images/9001/*.qcow2 local-lvm
qm set 9001 --scsi0 local-lvm:vm-9001-disk-0 --boot order=scsi0
qm set 9001 --net0 virtio,bridge=vmbr0
qm set 9001 --ide2 local:iso/virtio-win.iso,media=cdrom
```

---

## 🪄 5. Boot and finalize in Proxmox

1. Start the VM.  
   - If the PowerShell prep script was used → Windows should boot normally.  
   - If not → boot once from the Windows ISO, open a repair prompt, and inject the drivers manually:

   ```cmd
   dism /image:C:\ /add-driver /driver:D:\viostor\w11\amd64 /forceunsigned
   dism /image:C:\ /add-driver /driver:D:\NetKVM\w11\amd64 /forceunsigned
   ```

2. Once booted, run:
   ```
   D:\virtio-win-guest-tools.exe
   ```
   (installs QEMU Guest Agent, Balloon, network, and display drivers)

---

## ⚙️ Optional: VMDK import (manual method)

If you prefer manual import:

```bash
scp /vmfs/volumes/datastore1/WIN2025-SRV/*.vmdk root@pve01:/var/lib/vz/images/9001/
qm importdisk 9001 /var/lib/vz/images/9001/WS2025.vmdk local-lvm
qm set 9001 --scsi0 local-lvm:vm-9001-disk-0 --boot order=scsi0
```

Then attach the VirtIO ISO and repeat the driver installation steps inside Windows.

---

## 💡 Tips

- Always set your Proxmox disk controller to **VirtIO-SCSI**.
- For best performance use **VirtIO (paravirtualized)** NIC.
- Once migrated, snapshot and back up from Proxmox before deleting the ESXi copy.
- You can repeat the same process for Linux VMs — no VirtIO ISO needed.

---

### ✅ Example network bridge config (for VLANs)

If your 10-GbE trunk carries all VLANs and you need VLAN-specific bridges:

```ini
auto ens1f0
iface ens1f0 inet manual

auto ens1f0.120
iface ens1f0.120 inet manual
    vlan-raw-device ens1f0

auto vmbr120
iface vmbr120 inet manual
    bridge-ports ens1f0.120
    bridge-stp off
    bridge-fd 0
```

VMs connected to `vmbr120` will automatically be placed in VLAN 120.

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### 🏁 Result

After these steps:
- Your Windows Server 2025 VM boots on Proxmox without BSOD.
- Disk and network use VirtIO drivers.
- QEMU Guest Agent works (clean shutdowns, IP reporting).
- Migration from ESXi to Proxmox completed with full functionality.

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