Installing Proxmox VE 9.x on Debian with full disk LUKS (manual install)

[SuperNoobProx]

Hi,

I would like to ask for confirmation and best practices regarding
installing Proxmox VE 9.x on top of an existing Debian installation
with full disk encryption (LUKS).

Current situation:
- Hardware: Dell workstation / server (single NVMe disk)
- OS: Debian (clean install)
- Disk layout: full disk LUKS, unlocked manually at boot via console
- Boot mode: UEFI
- Filesystem: ext4 inside LUKS
- No hardware RAID
- ZFS is not required for my use case

Important note:
While testing the Proxmox VE installer (GUI), I could not find any
explicit "Encrypt" or "LUKS" option when selecting ext4 or XFS.
Encryption options only appear to be available when choosing ZFS,
which is why I am evaluating the manual installation approach.

Constraints / goals:
- I do NOT want to repartition or reinstall the system
- I explicitly want to keep LUKS encryption at boot
- I am aware that the Proxmox installer would overwrite the disk
- I prefer not to use ZFS unless strictly required

Planned approach:
- Install Proxmox VE via APT on top of the existing Debian system
- Use the official Proxmox repositories
- Keep the current encrypted disk layout unchanged

Questions:
1) Is this setup fully supported and stable with Proxmox VE 9.x?
2) Are there any specific caveats compared to the Proxmox installer
(e.g. initramfs, bootloader, systemd, kernel handling)?
3) Anything special to take care of regarding LUKS + Proxmox updates?
4) Is this approach acceptable for long-term / production use?

Thanks in advance.

 

[fstrankowski]

1) Is this setup fully supported and stable with Proxmox VE 9.x?

No and generally yes

2) Are there any specific caveats compared to the Proxmox installer
(e.g. initramfs, bootloader, systemd, kernel handling)?

Depends on on your specific case but generally no.

3) Anything special to take care of regarding LUKS + Proxmox updates?

No.

4) Is this approach acceptable for long-term / production use?

No.

That one was easy It should not cause any difficulties but yet its not a supported installation. But due to the fact that
Proxmox supports installation on top of a running Debian, this should be fine. I had a few of these running for years without major problems.

I'd suggest you add Busybox so you can decrypt the box via SSH and do not have to visit your console every time you reboot the machine.