How to Switch Between LightDM and GDM on Ubuntu

Changing your display manager to customize your Linux PC is easy. This is how you can switch between LightDM and GDM on Ubuntu.

The display manager is the graphical interface you use to enter your credentials when you log into your system. Knowing how to change the display manager is useful when you want to customize your desktop, since the login screen is a key aspect of a Linux desktop.

Although GDM, the default display manager on Ubuntu, comes out of the box, you can quickly switch between LightDM and GDM if you like.

Switch between LightDM and GDM on Ubuntu

The command you use to change the display manager is dpkg-reconfigure. As the name suggests, it reconfigures the packages after they have been installed on your system.

Note that the following command assumes you have at least two display managers installed on your computer. If you only have GDM installed, the command will exit with no output.

sudo dpkg-reconfigure gdm3

You will see an ncurses-based interactive interface that describes some display manager basics and shows how to use multiple display managers in Linux. To mark OK and press Enter keep going.

The system will display a list of all currently installed display managers on the Configure gdm3 Screen. Here you need to highlight and select the display manager you want to use. Choose light dim and hit Enter.

Restart your computer for the changes to take effect.

Note that the process of changing display managers is more or less the same on other Debian-based distributions, including Kali Linux. All you have to do is install and select a different display manager on the GDM configuration screen.

If you want to disable LightDM and switch back to GDM, run the following command again:

sudo dpkg-reconfigure gdm3

Then follow the same steps as above to switch back to GDM.

Changing display managers and login screens on Linux

Customizing the login screen is a rudimentary step in personalizing your Linux desktop. There are several Linux display managers to choose from. GDM, LightDM and SDDM are some of the best known.

When it comes to GUI and desktops, Linux has many terminologies that may seem similar to a beginner’s eye. Display managers, desktop environments, display servers, and window managers—although they may look and sound the same, they differ from others in more ways than one.