Ubuntu 16.04 LTS Server can be upgraded to the new Ubuntu release 18.04 Bionic Beaver with the steps provided in this post. Those who will like to try the new Ubuntu 18.04 LTS can also use this post to upgrade their Ubuntu version to Ubuntu 18.04 LTS development release.
Ubuntu 18.04 LTS has been released on April 26th, 2018 as planned and it will be supported for 5 years. To enjoy the new ubuntu associated with it, you will have to upgrade to this version of Ubuntu.
You can easily upgrade from Ubuntu 16.04 LTS to 18.04 LTS, even though 17.04 or 17.10 are not LTS version we can also upgrade to those as well.
It is recommended that you update your current version of the Ubuntu Server before proceeding with any of the steps in this post. To update Ubuntu use the following commands below:
sudo apt update && sudo apt upgrade && sudo apt dist-upgrade && sudo apt autoremove
You probably have Ubuntu Update Manager installed on your machine but if you don’t have then the following commands will be helpful for you.
sudo apt-get install update-manager-core
After installing update-manager, we need to make sure that the update-manager is configured for Long-term support (LTS). So make sure Prompt is set to lts. Then check with the following command:
sudo nano /etc/update-manager/release-upgrades
Ensure that Prompt equaled lts.
Now, we can be sure that our system is ready for the upgrade. To begin, run the command below to upgrade your Ubuntu to the latest development release.
sudo do-release-upgrade -d
Follow the upgrade wizard on your screen and answer the questions asked. When asked whether you wish to upgrade type y for yes.
This might take some time depending on your internet speed. New packages will be installed and you will be prompted to remove obsolete packages. Type y to remove obsolete packages.
Wait for the installation to be complete and when prompt to restart type
y to finish the installation and reboot the computer.
Your system should be upgraded to the latest ubuntu, Ubuntu 18.04 LTS.
According to Ubuntu wiki the support lifespan of Ubuntu 18.04 LTS :
The ‘main’ archive of Ubuntu 18.04 LTS will be supported for 5 years until April 2023. Ubuntu 18.04 LTS will be supported for 5 years for Ubuntu Desktop, Ubuntu Server, and Ubuntu Core. Ubuntu Studio 18.04 will be supported for 9 months. All other flavors will be supported for 3 years. ubuntu wiki
Now that you have completed the steps to upgrading your Ubuntu, you should notice that your login screen is different. The system may switch automatically from Unity to Gnome for you. Depending on your choices during the Ubuntu distribution upgrade, the system may automatically make the switch from Unity to GNOME for you.