The Ubuntu developers are moving quickly to bring you the absolute latest and greatest software the Open Source community has to offer. The Natty Narwhal Alpha 3 Release of Ubuntu 11.04, is a developer snapshot to give you an early glance at the next version of Ubuntu.
Upgrading from Ubuntu 10.10 to ubuntu 11.04
To upgrade from Ubuntu 10.10 on a desktop system, press Alt+F2 and type in "update-manager -d" (without the quotes) into the command box. Update Manager should open up and tell you: New distribution release ‘11.04' is available. Click Upgrade and follow the on-screen instructions.
To upgrade from Ubuntu 10.10 on a server system: install the update-manager-core package if it is not already installed; launch the upgrade tool with the command sudo do-release-upgrade -d; and follow the on-screen instructions. Note that the server upgrade is now more robust and will utilize GNU screen and automatically re-attach in case of e.g. dropped connection problems.
To upgrade from Xubuntu 10.10, follow the instructions above for Ubuntu 10.10.
Download the Alpha 3
This release is for developers only.
You can download Alpha 3 ISOs from:
http://cdimage.ubuntu.com/releases/natty/alpha-3/ (Ubuntu Desktop and Server)
http://uec-images.ubuntu.com/releases/natty/alpha-3/ (Ubuntu Server for UEC and EC2)
http://cdimage.ubuntu.com/ubuntu-netbook/releases/natty/alpha-3/ (Ubuntu Netbook ARM)
http://cdimage.ubuntu.com/kubuntu/releases/natty/alpha-3/ (Kubuntu)
http://cdimage.ubuntu.com/xubuntu/releases/natty/alpha-3/ (Xubuntu)
http://cdimage.ubuntu.com/edubuntu/releases/natty/alpha-3/ (Edubuntu DVD)
http://cdimage.ubuntu.com/ubuntustudio/releases/natty/alpha-3/ (Ubuntu Studio)
http://cdimage.ubuntu.com/mythbuntu/releases/natty/alpha-3/ (Mythbuntu)
this link is dead => http://cdimage.ubuntu.com/releases/natty/alpha-3/ (Ubuntu Desktop and Server)