Upgrading our Ubuntu Linux installtion (be it 10.04, 10.10, 11.04 or 11.10) can be fairly easy with the aid of the graphical update manager tool. However, in some cases the CLI (command line interface) is the only viable option for us to make a full distributional upgrade. To do this, first we need to login via one of the terminals (the command can also be issued via remote login – ssh for example – however, it is not that much recommended as when something goes wrong, there is not much that can be remedied without physical access to the host).
The upgrade command looks like this (issued by a user within the sudoers group):
sudo do-release-upgrade -d