Display manager, also known as login manager, provides a interface for users to input their user name and password. When account authetication is successful, it starts a session (window manager or desktop environment), such as GNOME shell, KDE Plasma or Deepin desktop environment.
A graphics server can only be managed by one display manager in one time. This, however ,does not prevent several display managers to be installed in one system.
Types of display manager
There are many kinds of display manager, for example:
- LightDM: default display manager used by deepinn and Ubuntu
- GDM：default display manager used by Gnome desktop environment
- SDDM: default display manager used by KDE Plasma desktop
Switching display manager
deepin offers LightDM as its default display manager. If you want to change it to another one, please follow the instruction below.
The first method
When installing display manager, a dialog will be shown to let you choose preferred display manager. Press TAB to choose one you would like to use, then Enter.
The second method
Launch the terminal, then execute:
sudo dpkg-reconfigure gdm # You can change "gdm" to any other display manager you like
After that, you will see the same dialog shown to you in the installation process, where you can change the default display manager.
Problem of display manager
System startup error: Checking Battery State ...
If you cannot login through graphical interface, please press Ctrl-Alt -F1 to enter tty1, login with your user name and password, then execute:
sudo apt-get install gdm sudo dpkg-reconfigure gdm
Use TAB to choose "LightDM", then press Enter. Press Alt-F7 to resume to graphical interface.