Upgrade to Ubuntu 15.04 “Vivid Vervet” – Here’s is how to upgrade to Ubuntu 15.04 from Ubuntu 14.10 and Ubuntu 14.04. You can upgrade Ubuntu 14.10/14.04 to Ubuntu 15.04 “Vivid Vervet” in easy manner.
If you are using either Ubuntu 14.04 or Ubuntu 14.10 and want to upgrade to Ubuntu 15.04, you have to perform a regular system upgrade:
sudo apt-get update
sudo apt-get dist-upgrade
If your system doesn’t have the update-manager-core installed, run the following command to install and run the upgrade:
sudo apt-get install update-manager-core
sudo do-release-upgrade -d
The d-release-upgrade command looks for the latest stable version of Ubuntu available. The -d command argument tells the upgrader to include the unstable versions also.
Ubuntu 15.04 Vivid Vervet, scheduled for release on the 23rd of April, 2015.