Advanced Migration Techniques to Proxmox VE

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There are various ways to migrate existing servers to Proxmox VE. They can be divided into two categories:

Physical-to-Virtual (P2V)
Migration of physical servers to Proxmox VE
Virtual-to-Virtual (V2V)
Migration of virtual machines and containers from other hypervisors to Proxmox VE

Physical-to-Virtual (P2V)

Follow these how-to for a P2V migration, to turn a physical machine into a Proxmox VE hosted virtual machine.

Clonezilla Live CDs

This method is fast, reliable and OS independent as it uses live CDs.

  • Get a live Linux CD like Clonezilla.
  • Prepare the source host, make sure that you have standard IDE drivers enabled (for WinXP/Win2003 use the mergeide.reg (, for W2k I followed this link (solution 2 worked for me): [1]
  • Now, boot the physical host with Clonezilla, go for the beginner mode and select device - device and then remote, just follow the wizard
  • On the Proxmox VE host, prepare a KVM guest, make sure you got a big enough IDE disk assigned (add 1 GB extra to be on the safe side) and also boot this KVM guest with the Clonezilla live CD and execute a shell.
  • Become root and run fdisk (e.g., fdisk /dev/sda) to make sure that sda is here, exit fdisk by entering w and pressing enter, this is essential.
  • Now enter all commands that wizard on the source server instructs you too to configure the network and then start the disk copy.
  • After the clone operation succeeded, stop the VM, then change the boot device to the hard disk in the VM "Options" panel, and then start the VM again. Windows should install all needed drivers automatically, just the Intel NIC drivers for e1000 must be loaded from ISO

VMware Converter

Physical (running) Windows server to Proxmox VE (KVM) using VMware vCenter Converter Standalone Client (V5)

Tested on an HP ProLiant ML350 G5 and G6

Prepare Windows

VMware vCenter Converter Standalone Client

  • Download here(version 5.x is Free Software and also free of charge but you need to create an account and login before download)


Prepare location to save local image

This guide is using an external USB Hard Drive. You may also save to a mapped network share.

NOTE Although the final image will be around the same size as the actual amount of data on the server, the Proxmox VE server should have enough free space to fit the total physical disk of the server unless you plan to shrink the windows disks. once migrated to Proxmox VE.

VMware vCenter Settings

Launch VMware vCenter and use the following settings:

  • Source type: Powered-on machine
  • Specify the powered-on machine: This local machine
  • Select destination type: VMware Workstation or other VMware virtual machine
  • Select VMware Product: VMware Workstation 8.0.x
  • Name: Enter the desired name for the image
  • Select a location for the virtual machine: Browse to the USB or Network drive where the image will be saved.

The next screen shows the settings for the virtual machine.

Click on "Advanced options", select the Post-conversion tab and make sure ‘Install VMware Tools on the destination virtual machine’ is NOT check. We do not want to install VMware tools.

Click next and then "Finish".

It will now convert your physical machine to a .vmdk file.

NOTE: Depending on your hardware, you may need to boot the .vmdk file using VMware Workstation or Player before moving the file to the Proxmox VE server. This allows windows to install additional drivers for the disk controller. If promoted to convert the disk to Workstation 9.x compatibility, say Yes. You won't know if you need this step until starting the Windows VM in the final step. If you get a blue screen during boot, you should try this step.

Prepare the VM on Proxmox VE

Create a new KVM virtual machine. You’ll want to use similar CPU and memory as the physical system. In the Hard Disk menu, leave everything as default. We won’t be using the disk created by Proxmox VE. Finish creating the VM. Make note of the VMID. For this guide, we’ll be using 100 as an example.

Once the VMware converter has completed, disable all of the networks adapters on the physical server and shut down. Disabling the network adapters will avoid potential IP conflicts if you will start the physical server back into Windows after you have your new virtual server running.

Move the image to the Proxmox VE Server

Plug a USB Hard Drive into the server

From the Proxmox VE command line:

mkdir /mnt/usb
mount /dev/sdc1 /mnt/usb/
ls /mnt/usb

You should see the contents of the USB drive. In my case, the vmdk file was located in /mnt/usb/windows-server/

Converting to qcow2

We want to convert the .vmdk image file to qcow2. To do this, use the following command:

qemu-img convert -f vmdk /mnt/usb/windows-server/windows-server.vmdk -O qcow2 /var/lib/vz/images/100/windows-server.qcow2

This can take a while depending on the size of file and speed of your system.

Final Steps

Once the conversion is complete, we need to edit the configuration file for the VM.

nano /etc/pve/local/qemu-server/100.conf

In the line with ide0: we want to change vm-100-disk-1.raw,size=32G to windows-server.qcow2

You may delete the empty disk created by Proxmox VE when you created the VM.

rm /var/lib/vz/images/100/vm-100-disk-1.raw

Start the VM and open the console. Windows should boot up normally. It’ll take a few minutes to detect the hardware changes. If the Windows system had a static IP address, you'll have to reconfigure the settings.

Alternative Methods

Virtual-to-Virtual (V2V)

Follow these how-to for a V2V migration, to move a virtual machine (VM) from another hypervisor to VM on Proxmox VE.


This explains the migration from a VMware ESXi 6.7 hypervisor to Proxmox VE 6.1. It is tested with guests with the following operating systems:

  • Debian 10
  • Windows 10 Pro
  • Windows Server 2016 Standard



In VMware ESXi navigate to your virtual machine in the tree on the left. Choose Actions->Export. This will download disk images and information about your virtual machine in the .ovf format in the browser. Move those files to a storage that is accessible by your Proxmox VE host.


Install VMware's ovftool on your Proxmox VE host. ovftool version 4.4 has been reported to work with the following versions of ESXi: 6.5 and 6.7. Others (for example, 6.0) might crash with an unhelpful error message

Remove any attached disk or ISO from your ESXi VM and run

ovftool vi://root@<ip-of-esxi>/<name-of-a-virtual-machine> .

to export a virtual machine from ESXi directly into your current directory.

You can replace the dot with any other path, for example "/mnt/pve/<some-storage>". This way you can export directly to a storage that you created in Proxmox VE.

Yellowpin.svg Note: You have to extract .ova archives

With some configurations you get a single (.ova) archive file that contains all .vmdk disk images and the small XML description .ovf file. If this is the case, then you have to extract it before you continue with qm importovf.


Go to the command line interface of Proxmox VE. Use the command qm importovf <new-vmid> </path/to/file.ovf> <storage> to import the virtual machine. For example:

qm importovf 200 /tmp/exported-vm.ovf local-lvm

This will create a new virtual machine using cores, memory and VM name as read from the OVF manifest, and import the disks. You have to configure the network manually. You can find syntax and an example on how to use this command on its man page.

Yellowpin.svg Note: Windows guests require a few additional steps

If you are migrating a Windows guest, you additionally have to execute the following commands. This example assumes that your imported virtual machine has the ID 130.

  • Use UEFI instead of BIOS for the virtual machine:
qm set 130 --bios ovmf
  • Windows requires additional drivers to use SCSI. Therefore, you should temporarily use SATA instead. In the following command, 'scsi0' should be replaced with the drive that's used to boot Windows.
sed -i 's/scsi0:/sata0:/' /etc/pve/qemu-server/130.conf

This will give you a initial working version. You can then improve your experience and access remaining SCSI drives by installing additional drivers as explained in Windows 10 guest best practices.

Server self-migration

It is also possible to migrate without the need to export each VM separately including virtual disks.
This way, you can convert a server from vSphere to Proxmox VE without the need of a second server.
For this process your vSphere should use VMFS6 and you need at least one empty HDD.
1. Export the VM information without the disks using ovftool (you still need to configure the network configuration for each VM).

ovftool --noDisks vi://root@<ip-of-esxi>/<name-of-a-virtual-machine> .

2. Install Proxmox VE on some disk that does not contain any important data. You don't need vSphere anymore at this point. If you have an OS disk with only vSphere on it, then you can now overwrite it with Proxmox VE.

Warning: Do not use/touch any other existing drives which are VMFS formatted

3. Create a directory on the above mention spare HDD.
4. Install vmfs6-tools which you need to mount (ready-only) the VMFS-formatted drives with the vSphere virtual disks.

apt install vmfs6-tools -y

5. List all available drives to identify the VMFS formatted ones

fdisk -l

6. Mount the VMFS disk partition (note it is read only)

vmfs6-tool /dev/<device><partition>

7. Convert the vSphere disk to a suitable format for Proxmox VE

qemu-img convert -f vmdk <path to your vmdk file>.vmdk -O <raw/qcow2> <path to your empty directory>.raw/qcow2 -p 

8. While the conversion is in progress you may create the 1st VM from ovf

qm importovf 200 /tmp/exported-vm.ovf

9. As soon as the conversion is finished you may mount the new Proxmox VE disk image to the VM.

qm rescan

If all VM images have been moved away from a VMFS6 disk, you can format it and use it at Proxmox VE


This explains the migration from a Hyper-V on Windows 10 hypervisor to Proxmox VE 6.1. It is tested with a Proxmox VE 6.1 guest.

Proxmox VE uses qemu-img to import disks. In my tests it supported .vhdx even though some sources don't explicitly list .vhdx as supported format. There are additional options if this should not work anymore:

  • Convert-VHD is a command line tool that is built-in in Windows and converts .vhdx to .vhd. This format is supported by qemu-img.
  • StarWind V2V Converter is a graphical tool that can create .qcow2 disks from Hyper-V guests.

In Hyper-V-Manager choose "Export..." at the right side and then a destination. While many files (for example for snapshots) will be exported, we are only interested in the .vhdx file(s). Move those files to a storage that is accessible by your Proxmox VE host. You will have to recreate the virtual machine settings yourself.

Go to the GUI of Proxmox VE and create a new virtual machine. We don't need the hard disk that the virtual machine creation wizard created. Delete it in the hardware options of the virtual machine.

Now go to the command line interface of Proxmox VE. Use the command "qm importdisk" to import the .vhdx virtual hard disk. You can find syntax and an example on how to use this command on its man page.


XEN also uses qemu disk format, so it should work in the same manner as described under "VMware to Proxmox VE".

You could use xenmigrate to do it.


Those are the necessary steps to migrate a Ubuntu Bionic VM from FreeNAS 11.2 to Proxmox VE 6.2-1. The VM in FreeNAS was created with the following parameters

  • Boot Loader Type: UEFI
  • Guest OS: Ubuntu Bionic
  • Disk
    • Disk Mode: AHCI
    • Zvol: test/ubuntu-1xmtpt

Check the name of your zvol by going to Virtual Machines → Options of the VM ⋮→ Devices → Options of your disk ⋮ → Edit → Zvol

Preparation in FreeNAS

  1. Create a shared directory in Sharing → Unix (NFS) Shares with path /mnt/test.
  2. Enable SSH in Services & edit the SSH service (Actions) to allow password login for root
  3. Copy the zvol to the shared directory
    1. Log in to FreeNAS via SSH
      ssh root@ip.of.your.freenas
    2. Copy the zvol to the shared directory
      dd if=/dev/zvol/test/ubuntu-1xmtpt of=/mnt/test/ubuntu.raw bs=1m

Importing to Proxmox VE

  1. Create a virtual machine (here vmid is 103) in Proxmox VE. Make sure to set BIOS to OVMF (this is UEFI).
  2. Delete the disk that was created in step 1.
  3. Create a directory mkdir /home/user/freenas
  4. Mount the shared directory from FreeNAS
     sudo mount -t nfs /home/user/freenas
  5. Import the image of the FreeNAS VM to the Proxmox VE VM as unused disk (vmid 103, storage local)
    qm importdisk 103 /home/user/freenas/ubuntu.raw local --format qcow2
  6. In the GUI of Proxmox VE:
    1. Go to the hardware view of your new virtual machine
    2. Set the display to spice
    3. Double click on the unused disk to attach it and choose Virtio as bus
    4. Go to the options view of your new virtual machine
    5. Choose your new virtio disk as bootdisk


The last released version of Red Hat Enterprise Virtualization (RHEV) is out of full support since August 2022[1] and you might want migrate to a supported Proxmox VE releases earlier than it's EOL date.

To move existing VMs you need to export them as OVA (archived docs). You should be able to do so by selecting the virtual machine, use the More Actions menu and there click on Export to OVA and use a directory or share that PVE either can directly access or easily moved later on.

On the Proxmox VE side you can extract the OVA, for example with tar xf exported-vm.ova for the more common tar format (or unzip if compressed as zip archive).

Then you can use qm importovf VMID /path/to/extracted.ovf and qm importdisk VMID PATH/TO/DISK.img STORAGE-ID


  1. Create an new VM on Proxmox VE
  2. add the existing disk image to the new VM
  3. add network, usb, pcie, ... devices as they where in the original VM
  4. set the boot order and adapt other options
  5. start the VM

Basic Example, Step-by-Step:

First a VM has to be created, for that you need to select an unused VMID (e.g., use pvecm nextid.

qm create 120

In the next step the some-image.img refers to the disk image you want to import and the some-storage refers to the name of a target storage, as listed in pvesm status. Please adapt those to the respective values.

qm disk import 120 some-image.img some-storage

Please note that qm importdisk adds the image as unused disk to the virtual machine, you can re-attach it to the VM via the web-interface.

You also need to mark it as a boot-disk, this can be done by using qm set 120 --boot order=scsi0.

qm set 120 --scsi0 some-storage:vm-120-disk-0

Basic Example: All-in-One:

Since Proxmox VE 7.2 you can use the qm create command to achieve all steps in one go:

qm create VMID --scsi0 STORAGE:0,import-from=/PATH/TO/DISK.IMG --boot order=scsi0

Please replace ALL-CAPS parts with the respective value. After that you can adapt the remaining basics (memory, vCPU core count, vNICs, ...) via the web-interface.

Further information

If your use case is not covered by this article you should check out the additional ways to migrate to Proxmox VE in the wiki. It gathers years of knowledge for cases which are not as common as the ones explained here, but sometimes is also rather outdated.

See Also