Failed upgrade from Lucid to Precise

[ogenex]

Attempting an upgrade from 10.04.4 LTS to 12.04 through the update manager results in a non-bootable system. The / partition is not found for some reason. Switching into the command line and performing an upgrade results in an error:

$ apt-get -f upgrade

E: Could not perform immediate configuration on 'python2.7-minimal'. Please see man 5 apt.conf under APT::Immediate-Configure for details. (2)

Attempting to reinstall python2.7-minimal (and python-minimal) didn't work either:

$ apt-get install -o APT::Immediate-Configure=false -f --reinstall python2.7-minimal

E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).

Attempting a do-release upgrade completes with errors, although the system is now unbootable. I have attached the contents of /var/log/dist-upgrade.

[ogenex (ogenex)]

On reboot the system is now enters intitramfs, not sure where to go from here, any help would be greatly appreciated.

[Matthias Klose (doko)]

if the system is unbootable, this has nothing to do with python-defaults.

[Jonathan Precise (jono-software-01)]

This is a bug in update-manager, as upgrades from an ubuntu version older than 11.10 use update-manager.