Display manager

A display manager, sometimes known as login manager or abbreviated as DM, presents the user with a graphical login screen to start an X server session.

Display Managers in Portage
More than half a dozen display managers are avaiable in the Portage tree. The following is a list (non-exaustive) of display managers available in the Portage tree:


 * GDM (Gnome Display Manager) –
 * KDM (KDE Display Manager) –
 * LXDM (LXDE Display Manager) –
 * Qingy (Qingy Is Not GettY) –
 * XDM (X Display Manager) –
 * CDM (The Console Display Manager) –
 * LightDM (A Lightweight Display Manager) –
 * SDDM (Simple Desktop Display Manager) –
 * SLiM (Simple Login Manager) –
 * WDM (WINGs Display Manager) –

Configuration
In major Linux operating systems display managers are started automatically on boot. In order for this to happen automatically a script must be added to the proper init system's runlevel. Examples for OpenRC and Systemd are provided below.

Be careful to read the documentation for each display manager, as sightly different configuration will be required. For more information see the respective wiki entry for the display manager of choice.

OpenRC
Under most circumstances the OpenRC init system (Gentoo's default init system) will be used to start the display manager. The XDM init script handles the starting of the display manager. Configuration of this file is needed to set a default display manager for the system.

The following examples will set KDE to be the default display manager. Adjust as necessary for other display managers.

To start KDM on boot, add the XDM init script to the system's default runlevel:

To start KDM immedately, run:

Systemd
If using systemd as the init system, first locate a file. Some can be found in the systemd overlay. Choose one that works move it to or install  from the overlay.

To start KDM on boot, enable the following service:

To start KDM immediately run this command:

Start X without a Display Manager
See the X without Display Manager article.