LightDM is a lightweight, cross-desktop display manager. A display manager is a daemon that:
Key features of LightDM are:
The core LightDM project does not provide any greeter with it; you should install a greeter appropriate to your system. Popular greeter projects are:
LightDM configuration is provided by the following files:
/usr/share/lightdm/lightdm.conf.d/*.conf
/etc/lightdm/lightdm.conf.d/*.conf
/etc/lightdm/lightdm.conf
System provided configuration should be stored in /usr/share/lightdm/lightdm.conf.d/
. System administrators can override this configuration by adding files to /etc/lightdm/lightdm.conf.d/
and /etc/lightdm/lightdm.conf
. Files are read in the above order and combined together to make the LightDM configuration.
For example, if a sysadmin wanted to override the system configured default session (provided in /usr/share/lightdm/lightdm.conf.d
) they should make a file /etc/lightdm/lightdm.conf.d/50-myconfig.conf
with the following:
[Seat:*]
user-session=mysession
Configuration is in keyfile format. For most installations you will want to change the keys in the [Seat:*]
section as this applies to all seats on the system (normally just one). A configuration file showing all the possible keys is provided in data/lightdm.conf
.
LightDM can be configured to run an external shell script to setup displays.
If an display setup script is used, it must be:
/usr/share
lightdm
and group lightdm
To test a configuration:
xserver-xephyr
: sudo apt install xserver-xephyr
sudo -u lightdm lightdm --test-mode --debug
Put the shell script reference in the LightDM configuration:
[Seat:*]
display-setup-script=/usr/share/example_display_setup_script.sh
Stack Overflow and Ask Ubuntu are good sites for frequently asked questions.