You should consider replacing Proxmox with LXD/Incus because, depending in your needs, you might be able to replace your Proxmox instances with Incus and avoid a few headaches in the future.

While being free and open-source software, Proxmox requires a payed license for the stable version and updates. Furthermore the Proxmox guys have been found to withhold important security updates from non-stable (not paying) users for weeks.

Incus / LXD is an alternative that offers most of the Proxmox’s functionality while being fully open-source – 100% free and it can be installed on most Linux systems. You can create clusters, download, manage and create OS images, run backups and restores, bootstrap things with cloud-init, move containers and VMs between servers (even live sometimes).

Incus also provides a unified experience to deal with both LXC containers and VMs, no need to learn two different tools / APIs as the same commands and options will be used to manage both. Even profiles defining storage, network resources and other policies can be shared and applied across both containers and VMs. The same thing can’t be said about Proxmox, while it tries to make things smoother there are a few inconsistencies and incompatibilities there.

Incus is free can be installed on any clean Debian system with little to no overhead and on the release of Debian 13 it will be included on the repositories.

Another interesting advantage of Incus is that you can move containers and VMs between hosts with different base kernels and Linux distros. If you’ve bought into the immutable distro movement you can also have your hosts run an immutable with Incus on top.

Incus Under Debian 12

If you’re on stable Debian 12 then you’ve a couple of options:

• Run the LXD version provided on their repositories: this will give you LXD 5.0.2 LTS that is guaranteed to be compatible with Debian 13’s Incus. Note that this was added before Canonical decided to move LXD in-house;
• Use the backported version as described here: linuxcontainers.org/incus/docs/main/installing/;
• Get the latest Incus pre-compiled from github.com/zabbly/incus and install as described above.

In the first option you’ll get a Debian 12 stable system with a stable LXD 5.0.2 LTS, it works really well however it doesn’t provide a WebUI. The second and third options will give you the latest Incus but they might not be as stable. Personally I was running LXD from Snap since Debian 10, and moved to LXD 5.0.2 LTS repository under Debian 12 because I don’t care about the WebUI. I can see how some people, particularly those coming from Proxmox, would like the WebUI so getting the latest Incus might be a good option.

I believe most people running Proxmox today will, eventually, move to Incus and never look back, I just hope they do before Proxmox GmbH changes their licensing schemes or something fails. If you don’t require all features of Proxmox then Incus works way better with less overhead, is true open-source, requires no subscriptions, and doesn’t delay important security updates.

Note that modern versions of Proxmox already use LXC containers so why not move to Incus that is made by the same people? Why keep dragging all of the Proxmox overhead and potencial issues?