Comment 3 for bug 1918421

Unfortunately the patch to netplan.io in PR 202 has not quite fixed the original issue and actually breaks existing Jammy Pi installs when the package is upgraded. The version of /etc/netplan/10-rpi-ethernet-eth0.yaml shipped in the image uses the whitespace-separated driver line which the maintainers decided to disallow:

network:
  ethernets:
    eth0:
      # Rename the built-in ethernet device to "eth0"
      match:
        driver: bcmgenet smsc95xx lan78xx
      set-name: eth0
      dhcp4: true
      optional: true

This style was accepted by netplan.io versions prior to 0.104-0ubuntu1 (although it didn't actually match the driver correctly), but the new version rejects the existing configuration file entirely, failing with the error "A 'driver' glob cannot contain whitespace". After upgrading packages on my Jammy Pi installation with sudo apt upgrade, the network did not come up automatically on the next reboot, and I could only recover the install by connecting HDMI / USB to debug.

The fix was to simply replace the driver line with:

        driver: ["bcmgenet", "smsc95xx", "lan78xx"]

Either netplan.io needs to accept whitespace-separated driver lists after all, or the 10-rpi-ethernet-eth0.yaml file shipped with the Ubuntu Pi image needs to be updated to use a YAML-conforming list (and if possible this file should be automatically patched when upgrading existing installs).