Difference between revisions of "LightDM"

Revision as of 21:51, 27 December 2018

Other languages:

Resources

Home

Wikipedia

Open Hub

LightDM is a cross-desktop display manager whose aim is to be the standard display manager for the X server.

The key features (as listed by upstream) include:

A well-defined greeter API allowing multiple GUIs.
Support for all display manager use cases, with plugins where appropriate.
Low code complexity.
Fast performance.

Installation

USE flags

USE flags for x11-misc/lightdm A lightweight display manager

`audit`	Enable support for Linux audit subsystem using sys-process/audit
`elogind`	Enable session tracking via sys-auth/elogind
`gnome`	Add GNOME support
`gtk`	Pull in the gtk+ greeter
`introspection`	Add support for GObject based introspection
`non-root`	Use non-root user by default
`qt5`	Add support for the Qt 5 application and UI framework
`systemd`	Enable use of systemd-specific libraries and features like socket activation or session tracking
`vala`	Enable bindings for dev-lang/vala

Data provided by the Gentoo Package Database · Last update: 2024-01-17 14:07 More information about USE flags

Emerge

Install lightdm:

root #emerge --ask x11-misc/lightdm

Configuration

The (global) configuration file for LightDM can be found at:

/etc/lightdm/lightdm.conf

GTK+

The GTK+ greeter configuration can be modified by manually editing the following file:

/etc/lightdm/lightdm-gtk-greeter.conf

RazorQt

The RazorQt greeter currently does not offer any configuration options.

Boot service

OpenRC

Set LightDM as the default display manager:

FILE /etc/conf.d/xdm

DISPLAYMANAGER="lightdm"

To start LightDM on boot, add dbus and xdm to the default runlevel. dbus is necessary because LightDM depends on it to pass messages:

root #rc-update add dbus default

root #rc-update add xdm default

To start LightDM now:

root #/etc/init.d/dbus start

root #/etc/init.d/xdm start

systemd

To start LightDM on boot:

root #systemctl enable lightdm

To start LightDM now:

root #systemctl start lightdm

Command-line tool

LightDM includes a command-line tool, dm-tool, which can be used to switch user sessions, lock the current seat, etc. To see a list of available commands, use the --help option:

user $dm-tool --help

For example, to lock the current seat:

user $dm-tool lock

Tips

Running commands at log-in

A user can run some programs automatically when logging in using LightDM by adding commands in ~/.xprofile, which will be sourced by LightDM. For example:

FILE ~/.xprofile

# Starting redshift, setting the dpi with xrandr and set the brightness to 50% with xbacklight
xrandr --dpi 192 &
redshift-gtk &
xbacklight -set 50 &

Unlock GNOME Keyring

To unlock your GNOME Keyring (gnome-base/gnome-keyring) automatically on login, edit /etc/pam.d/lightdm to look as follows. Note: Lines ending with the comment #keyring should be added.

FILE /etc/pam.d/lightdm

auth	   include	system-local-login
auth       optional	pam_gnome_keyring.so #keyring
account    include	system-local-login
session	   include	system-local-login
session    optional	pam_gnome_keyring.so auto_start #keyring

Troubleshooting

Cursor themes not working

As of March 28, 2015, the stable versions of lightdm (lightdm-1.10.3) and lightdm-gtk-greeter (lightdm-gtk-greeter-1.7.0) have a bug that affects some DEs such as XFCE with setting the mouse cursor. Applications will apply the new mouse theme, but the root window where the window manager draws on does not. To get around this, simply unmask the latest versions (lightdm-1.13.2 and lightdm-gtk-greeter-2.0.0 at the time of writing) and the cursors will be set correctly.

More information can be found in Ubuntu's bug #1024482.