Upgrading from Ubuntu 22.04 to 24.04 breaks TLJH

[brucat]

Bug description

TLJH fails on upgrade form Ubuntu 22.04.5 LTS to 24.04.2 LTS

How to reproduce

A TLJH on Ubuntu 22.04 was upgraded to 24.04. The jupyter.service fails to start after upgrade.
I tried rerunning the installer but that failed. I removed the old TLJH install and tried a new install. That seemed to work, but neither the traefik nor jupyter services start

Expected behaviour

TLJH should continue to function on a Ubuntu version upgrade to the latest LTS

Actual behaviour

TLJH ails on upgrade

Your personal set up

Ubuntu 24.04.2 on a Thinkserver R640

• OS:

Ubuntu 24.04.2 on a Thinkserver R640

• Version(s):

Full environment

# paste output of `pip freeze` or `conda list` here

Configuration

# jupyterhub_config.py

Logs