One of the nice things about Ubuntu is how easy it makes it to upgrade between versions - typically start up update-manager and it will prompt you if there is a new version available and handle all the details of the upgrade for you. I've done numerous upgrades this way and never had any issues.

However, I have a number of ubuntu servers which I manage and previously I have upgraded them by changing the /etc/apt/sources.list and then running "sudo apt-get dist-upgrade"

Today I discovered that there is an automated script to handle it - which I presume is what powers the gui version behind the scenes.

You need to make sure you have update-manager-core installed:

Then you simply run do-release-upgrade

I've just upgraded two different servers from Feisty as it has recently stopped being supported. I upgraded them to Gutsy and then to Hardy which is a Long Term Supported version. The whole process took about an hour of which it took about 5 minutes of my attention to answer a few simple questions.

Who said Linux is hard :-) Cheers, Mark