With just a few hours till Ubuntu 11.04 is released, if you are one of these people who want to try out Ubuntu 11.04 but do not want to do a clean install, this post will tell you how you can upgrade from Ubuntu 10.10 to Ubuntu 11.04 painlessly.
There are two ways by which you can upgrade from Ubuntu 10.10 to Ubuntu 11.04.
Upgrade using an Ubuntu 11.04 CD image
If you have a CD image of Ubuntu 11.04, this might be a good way for you to update. Unlike in the earlier releases, you can also use the Ubuntu 11.04 installer disk to perform an upgrade. If you do not have the image, you can download it from here.
After downloading the image, burn it on a CD or make a bootable USB drive with it. To create a bootable USB drive from the Ubuntu image in Windows, read this guide. To do it in Ubuntu, use the Startup Disk Creator.
Put in the CD or plugin the USB drive and reboot your system. Make sure to boot using the CD or the USB drive.
The Ubuntu installer should start. Select Install Ubuntu and proceed with the installation until it ask you to allocate disk space. Here, select Upgrade Ubuntu 10.10 to Ubuntu 11.04. (Don't mind that it is written Upgrade 11.04 to Ubuntu 11.04 in the picture below. It is because I already have Ubuntu 11.04 installed.) Proceed as usual. After the upgrade is done, restart your system. You should have Ubuntu 11.04 now.
Upgrade using the Update Manager
If you have a fast internet connection, upgrading to Ubuntu 11.04 without downloading the ISO might be the way to go.
Press ALT+F2 and execute the command below:
The update manager should open and notify you that Ubuntu 11.04 is available. Click on Upgrade and it will take you through the required steps to upgrade to Ubuntu 11.04. After the upgrade is done, restart your system.