Skip to content

2026-06-29 OVH Dockers staging upgrade#

Dockers staging (or OVH200) is a VM running on OVH1.

This report describes the upgrade of OVH200 from Debian 11 to Debian 12.

Making the upgrade#

Here are the steps that were followed:

  • Create a Proxmox snapshot of OVH200 (without including RAM)
  • Upgrade the existing packages
sudo apt update
sudo apt upgrade
sudo apt full-upgrade
sudo apt autoremove --purge
  • Check the packages health. This shouldn't output anything.
sudo dpkg --audit
sudo apt-mark showhold
  • Change Debian repository sources
sudo sed -i 's/bullseye/bookworm/g' /etc/apt/sources.list
sudo sed -i '/non-free/ s/$/ non-free-firmware/' /etc/apt/sources.list
  • List package sources to update
ls /etc/apt/sources.list.d/
  • Change each repository sources (here is an example for docker)
sudo sed -i 's/bullseye/bookworm/g' /etc/apt/sources.list.d/docker.list
  • Upgrade the OS (in tmux in case the SSH connection breaks)
tmux
sudo apt update
sudo apt upgrade --without-new-pkgs
sudo apt full-upgrade
  • Reboot (this didn't work as expected, which is explained in the next part)
sudo reboot
  • Ensure everything runs correctly
lsb_release -a
sudo systemctl list-units --state failed
sudo docker ps -a
  • Clean up legacy packages
sudo apt autoremove --purge
sudo apt clean
  • I also installed the QEMU Guest Agent
sudo apt install qemu-guest-agent
sudo systemctl start qemu-guest-agent
sudo systemctl enable qemu-guest-agent

OVH200 not rebooting after upgrade#

For some unknown reason (probably related to the upgrade of the Linux kernel), the VM would not reboot after the upgrade.

OVH200 was stuck looping on the boot screen (showing the Proxmox logo). Here is how it was fixed:

  • In Proxmox, open the graphical console of the VM
  • Press Esc
  • Choose the Debian installer DVD: 3. DVD/CD [...] (Debian [..])
  • Choose Advanced options
  • Choose Rescue mode
  • Choose Do not configure the network at this time
  • Choose the device to use as root filesystem: /dev/sdb1
  • Choose Execute a shell in /dev/sdb1
  • Run the following commands:
grub-install /dev/sdb
update-grub
update-initramfs -u -k all
exit
  • Choose Reboot the system