Microsoft is updating the Secure Boot certificates originally issued in 2011 to ensure that Windows devices continue to verify trusted boot software. Because our servers are still running in Legacy BIOS mode, we must transition them to UEFI boot mode to maintain full Secure Boot compatibility. Therefore, we need the correct method to change a Proxmox Virtual Environment (PVE) virtual machine running Windows Server Standard 2022 from Legacy (SeaBIOS) to UEFI (OVMF).Can you assist with this on our server without losing data
Change a Proxmox Virtual Environment (PVE) virtual machine running Windows Server Standard 2022 from Legacy (SeaBIOS) to UEFI (OVMF).
- Thread starter Malvern Masiye
- Start date
Hey,
please don't cross-post your questions in different sub-forums simultaneously [1]. Also, this is the German language sub-forum. Hence, asking questions in English is not intended here.
Thanks for your understanding!
[1]: https://forum.proxmox.com/threads/c...2022-from-legacy-seabios-to-uefi-ovmf.182117/
please don't cross-post your questions in different sub-forums simultaneously [1]. Also, this is the German language sub-forum. Hence, asking questions in English is not intended here.
Thanks for your understanding!
[1]: https://forum.proxmox.com/threads/c...2022-from-legacy-seabios-to-uefi-ovmf.182117/
The in-place conversion is doable. First, inside the running Windows VM, convert the disk from MBR to GPT with the built-in tool:
Once that works, shut down the VM, then in the PVE config: change BIOS to OVMF, add an EFI Disk (on your storage, pre-enrolled keys), and set the disk bus to SCSI/VirtIO-SCSI if it isn't already. Boot order might need adjusting too.
Important: snapshot or backup the VM before you start. If mbr2gpt fails (e.g. too many partitions), you'll want a way back. Also, which PVE version are you on, and how many VMs need converting?
If you need help with multiple servers, B1 Systems (Proxmox partner) can help: https://www.b1-systems.de
Code:
mbr2gpt /convert /allowFullOSOnce that works, shut down the VM, then in the PVE config: change BIOS to OVMF, add an EFI Disk (on your storage, pre-enrolled keys), and set the disk bus to SCSI/VirtIO-SCSI if it isn't already. Boot order might need adjusting too.
Important: snapshot or backup the VM before you start. If mbr2gpt fails (e.g. too many partitions), you'll want a way back. Also, which PVE version are you on, and how many VMs need converting?
If you need help with multiple servers, B1 Systems (Proxmox partner) can help: https://www.b1-systems.de
But keep in mind that the EFI partition to be created is placed in the VM behind the actual data partition. This will shoot you in the foot if you want to expand the partition later. So it's best to expand this to a suitable size before making the change.
However, I have not yet tried removing an EFI partition, then enlarging the data partition and then creating the EFI partition again.
However, I have not yet tried removing an EFI partition, then enlarging the data partition and then creating the EFI partition again.
Last edited: