Upgrade Ubuntu from 10.04 to 10.10 From command line

Believe it or not, upgrading from command line is just as easy as it is from the GUI tool. The first step is to update your system. So open up a terminal window and issue this command:

sudo apt-get update

The first step is to issue the following command:

sudo apt-get install update-manager-core

nano /etc/update-manager/release-upgrades

This file determines the default behavior for the release upgrader. The line you need to change is at the bottom of this file. Change it from:

Prompt=lts

to

Prompt=normal

Save and close that file and then issue the command:

sudo do-release-upgrade -d

ที่มา http://www.ghacks.net/2010/09/28/upgrade-ubuntu-from-10-04-to-10-10/