Ubuntu - how to upgrade from 12.10 to 14.04

На чистой системе Ubuntu 12.10 делаем:

# nano /etc/apt/sources.list
###### Ubuntu Main Repos
deb http://us.archive.ubuntu.com/ubuntu/ trusty main restricted universe multiverse
deb-src http://us.archive.ubuntu.com/ubuntu/ trusty main restricted universe multiverse
###### Ubuntu Update Repos
deb http://us.archive.ubuntu.com/ubuntu/ trusty-security main restricted universe multiverse
deb http://us.archive.ubuntu.com/ubuntu/ trusty-updates main restricted universe multiverse
deb http://us.archive.ubuntu.com/ubuntu/ trusty-proposed main restricted universe multiverse
deb http://us.archive.ubuntu.com/ubuntu/ trusty-backports main restricted universe multiverse
deb-src http://us.archive.ubuntu.com/ubuntu/ trusty-security main restricted universe multiverse
deb-src http://us.archive.ubuntu.com/ubuntu/ trusty-updates main restricted universe multiverse
deb-src http://us.archive.ubuntu.com/ubuntu/ trusty-proposed main restricted universe multiverse
deb-src http://us.archive.ubuntu.com/ubuntu/ trusty-backports main restricted universe multiverse 

# apt-get update
# apt-get upgrade
# apt-get dist-upgrade

Проверяем:

# lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 14.04.1 LTS
Release:        14.04
Codename:       trusty