Upgrading Proxmox VE 8 to 9¶

Proxmox VE 9 (based on Debian 13 “trixie”) is supported for NETLAB+, validated on Proxmox VE 9.2.3 and later. Existing host servers running Proxmox VE 8.4 can be upgraded in place to Proxmox VE 9.x without reinstalling — there is no need to rebuild your hosts or re-import your NETLAB+ VM.

Note

Proxmox VE 8.4.x remains the baseline for fresh installs (see the Installation section). This Upgrade section is for administrators who already run a Proxmox VE 8.4 cluster and want to move to Proxmox VE 9.x.

What changes in Proxmox VE 9¶

The base operating system moves from Debian 12 (bookworm) to Debian 13 (trixie).
APT repositories move to the modern deb822 (.sources) format.
A newer Linux kernel is installed, which can change network interface names on some hardware (see Post-Upgrade Tasks).
Ceph, if used, must be on the Squid (19.2) release before upgrading.

Upgrade at a glance¶

The upgrade is performed from the shell of each Proxmox host, one node at a time:

Prerequisites & Preparation — update to 8.4.1+, back up, and run pve8to9.
Update the APT Repositories — switch from bookworm to trixie.
Perform the Upgrade — apt dist-upgrade and reboot.
Post-Upgrade Tasks — verify, re-run the NDG Post Install Script, and check networking.

Tip

Every step in this guide is a shell command. In the Proxmox web UI, open the host’s shell with the xterm.js console: select the node, click the arrow on the Shell button (top right), and choose xterm.js. Unlike the default noVNC console, xterm.js supports copy and paste, so you can paste the commands from this guide directly. (For the long dist-upgrade step itself, see the connection guidance on Perform the Upgrade.)

Danger

Do not begin the upgrade during an active class or lab reservation. Read the Prerequisites & Preparation page in full before you start, and ensure you have a tested backup of your NETLAB+ VM and pods.

Tip

This guide follows the official Proxmox VE 8 to 9 upgrade documentation, with guidance specific to NETLAB+ deployments.