Related articles
* [GNOME](/index.php/GNOME "GNOME")
* [Display manager](/index.php/Display_manager "Display manager")
From [GDM - GNOME Display Manager](https://wiki.gnome.org/Projects/GDM): "The GNOME Display Manager (GDM) is a program that manages graphical display servers and handles graphical user logins."
[Display managers](/index.php/Display_manager "Display manager") provide [X Window System](/index.php/X_Window_System "X Window System") and [Wayland](/index.php/Wayland "Wayland") users with a graphical login prompt.
## Contents
* [1 Installation](#Installation)
* [2 Starting](#Starting)
* [2.1 Autostarting applications](#Autostarting_applications)
* [3 Configuration](#Configuration)
* [3.1 Log-in screen background image](#Log-in_screen_background_image)
* [3.2 DConf configuration](#DConf_configuration)
* [3.2.1 Log-in screen logo](#Log-in_screen_logo)
* [3.2.2 Changing the cursor theme](#Changing_the_cursor_theme)
* [3.2.3 Larger font for log-in screen](#Larger_font_for_log-in_screen)
* [3.2.4 Turning off the sound](#Turning_off_the_sound)
* [3.2.5 Configure power button behavior](#Configure_power_button_behavior)
* [3.2.6 Enabling tap-to-click](#Enabling_tap-to-click)
* [3.2.7 Disable/Enable Accessibility Menu](#Disable.2FEnable_Accessibility_Menu)
* [3.3 Keyboard layout](#Keyboard_layout)
* [3.4 Change the language](#Change_the_language)
* [3.5 Users and login](#Users_and_login)
* [3.5.1 Automatic login](#Automatic_login)
* [3.5.2 Passwordless login](#Passwordless_login)
* [3.5.3 Passwordless shutdown for multiple sessions](#Passwordless_shutdown_for_multiple_sessions)
* [3.5.4 Enable root login in GDM](#Enable_root_login_in_GDM)
* [3.5.5 Hide user from login list](#Hide_user_from_login_list)
* [3.6 Setup default monitor settings](#Setup_default_monitor_settings)
* [3.7 Configure X server access permission](#Configure_X_server_access_permission)
* [4 Troubleshooting](#Troubleshooting)
* [4.1 Failure to use proprietary NVIDIA driver](#Failure_to_use_proprietary_NVIDIA_driver)
* [4.2 Failure on logout](#Failure_on_logout)
* [4.3 Rootless Xorg](#Rootless_Xorg)
* [4.4 Use Xorg backend](#Use_Xorg_backend)
* [4.5 Incomplete removal of gdm](#Incomplete_removal_of_gdm)
* [4.6 GDM auto-suspend (GNOME 3.28)](#GDM_auto-suspend_.28GNOME_3.28.29)
* [5 See also](#See_also)
## Installation
GDM can be [installed](/index.php/Installed "Installed") with the [gdm](https://www.archlinux.org/packages/?name=gdm) package, and it is installed as part of the [gnome](https://www.archlinux.org/groups/x86_64/gnome/) group.
If you would prefer to use legacy GDM which was used in GNOME 2 and has its own configuration utility, install the [gdm-old](https://aur.archlinux.org/packages/gdm-old/) package. Note that the rest of this article discusses current GDM, not legacy GDM, unless indicated otherwise.
You might also wish to install the following:
* **gdm3setup** — An interface to configure GDM3, autologin options and change Shell theme
[https://github.com/Nano77/gdm3setup](https://github.com/Nano77/gdm3setup) || [gdm3setup-utils](https://aur.archlinux.org/packages/gdm3setup-utils/)
## Starting
To start GDM at boot time [enable](/index.php/Enable "Enable") `gdm.service`.
### Autostarting applications
One might want to autostart certain commands, such as *xrandr* for instance, on login. This can be achieved by adding a command or script to a location that is sourced by the display manager. See [Display manager#Autostarting](/index.php/Display_manager#Autostarting "Display manager") for a list of supported locations.
**Note:** The `/etc/gdm/Init` directory is no longer a supported location, see [[1]](https://bugzilla.gnome.org/show_bug.cgi?id=751602#c2).
## Configuration
### Log-in screen background image
**Note:**
* Since GNOME 3.16, GNOME Shell themes are now stored as binary files (gresource).
* This change will be overwritten on subsequent updates of [gnome-shell](https://www.archlinux.org/packages/?name=gnome-shell).
Firstly, you need to extract the existing GNOME Shell theme to a folder in your home directory. You can do this using the following script:
`extractgst.sh`
```
#!/bin/sh
gst=/usr/share/gnome-shell/gnome-shell-theme.gresource
workdir=${HOME}/shell-theme
for r in `gresource list $gst`; do
r=${r#\/org\/gnome\/shell/}
if [ ! -d $workdir/${r%/*} ]; then
mkdir -p $workdir/${r%/*}
fi
done
for r in `gresource list $gst`; do
gresource extract $gst $r >$workdir/${r#\/org\/gnome\/shell/}
done
```
Navigate to the created directory. You should find that the theme files have been extracted to it. Now copy your preferred background image to this directory.
Next, you need to create a file in the directory with the following content:
`gnome-shell-theme.gresource.xml`
```
calendar-arrow-left.svg
calendar-arrow-right.svg
calendar-today.svg
checkbox-focused.svg
checkbox-off-focused.svg
checkbox-off.svg
checkbox.svg
close.svg
close-window-active.svg
close-window-hover.svg
close-window.svg
corner-ripple-ltr.png
corner-ripple-rtl.png
dash-placeholder.svg
filter-selected-ltr.svg
filter-selected-rtl.svg
gnome-shell.css
gnome-shell-high-contrast.css
icons/message-indicator-symbolic.svg
key-enter.svg
key-hide.svg
key-layout.svg
key-shift-latched-uppercase.svg
key-shift.svg
key-shift-uppercase.svg
logged-in-indicator.svg
no-events.svg
no-notifications.svg
**filename**
pad-osd.css
page-indicator-active.svg
page-indicator-checked.svg
page-indicator-hover.svg
page-indicator-inactive.svg
process-working.svg
running-indicator.svg
source-button-border.svg
summary-counter.svg
toggle-off-hc.svg
toggle-off-intl.svg
toggle-off-us.svg
toggle-on-hc.svg
toggle-on-intl.svg
toggle-on-us.svg
ws-switch-arrow-down.png
ws-switch-arrow-up.png
```
Replace **filename** with the filename of your background image.
Now, open the `gnome-shell.css` file in the directory and change the `#lockDialogGroup` definition as follows:
```
#lockDialogGroup {
background: #2e3436 url(**filename**);
background-size: **[WIDTH]**px **[HEIGHT]**px;
background-repeat: no-repeat;
}
```
Set `background-size` to the resolution that GDM uses, this might not necessarily be the resolution of the image. For a list of display resolutions see [Display resolution](https://en.wikipedia.org/wiki/Display_resolution#Computer_monitors "wikipedia:Display resolution"). Again, set **filename** to be the name of the background image.
Finally, compile the theme using the following command:
```
$ glib-compile-resources gnome-shell-theme.gresource.xml
```
Then copy the resulting `gnome-shell-theme.gresource` file to the `/usr/share/gnome-shell` directory.
Then restart `gdm.service` (note that simply logging out is not enough) and you should find that it is using your preferred background image.
For more information, please see the following [forum thread](https://bbs.archlinux.org/viewtopic.php?id=197036).
### DConf configuration
Some GDM settings are stored in a DConf database. They can be configured either by adding *keyfiles* to the `/etc/dconf/db/gdm.d` directory and then recompiling the GDM database by running `dconf update` as root or by logging into the GDM user on the system and changing the setting directly using the *gsettings* command line tool. Note that for the former approach, a GDM profile file is required - this must be created manually as it is no longer shipped upstream, see below:
`/etc/dconf/profile/gdm`
```
user-db:user
system-db:gdm
file-db:/usr/share/gdm/greeter-dconf-defaults
```
For the latter approach, you can log into the GDM user with the command below:
```
# machinectl shell gdm@
```
#### Log-in screen logo
Either create the following keyfile
`/etc/dconf/db/gdm.d/02-logo`
```
[org/gnome/login-screen]
logo='*/path/to/logo.png*'
```
and then recompile the GDM database or alternatively log in to the GDM user and execute the following:
```
$ gsettings set org.gnome.login-screen logo '*/path/to/logo.png*'
```
#### Changing the cursor theme
GDM disregards [GNOME](/index.php/GNOME "GNOME") cursor theme settings and it also ignores the cursor theme set according to the [XDG specification](/index.php/Cursor_themes#XDG_specification "Cursor themes"). To change the cursor theme used in GDM, either create the following keyfile
`/etc/dconf/db/gdm.d/10-cursor-settings`
```
[org/gnome/desktop/interface]
cursor-theme='*theme-name'*
```
and then recompile the GDM database or alternatively log in to the GDM user and execute the following:
```
$ gsettings set org.gnome.desktop.interface cursor-theme '*theme-name*'
```
#### Larger font for log-in screen
Click on the accessibility icon at the top right of the screen (a white circle with the silhouette of a person in the centre) and check the *Large Text* option.
To set a specific scaling factor, you can create the following keyfile:
`/etc/dconf/db/gdm.d/03-scaling`
```
[org/gnome/desktop/interface]
text-scaling-factor='*1.25*'
```
and then recompile the GDM database or alternatively log in to the GDM user and execute the following:
```
$ gsettings set org.gnome.desktop.interface text-scaling-factor '*1.25*'
```
#### Turning off the sound
This tweak disables the audible feedback heard when the system volume is adjusted (via keyboard) on the login screen.
Either create the following keyfile:
`/etc/dconf/db/gdm.d/04-sound`
```
[org/gnome/desktop/sound]
event-sounds='false'
```
and then recompile the GDM database or alternatively log in to the GDM user and execute the following:
```
$ gsettings set org.gnome.desktop.sound event-sounds 'false'
```
#### Configure power button behavior
**Note:**
* The [logind settings](/index.php/Power_management#ACPI_events "Power management") for the power button are overriden by GNOME Settings Daemon. [[2]](https://bugzilla.gnome.org/show_bug.cgi?id=755953#c4)
* As of GDM 3.18, the power button cannot be set to *interactive*. [[3]](https://bugzilla.gnome.org/show_bug.cgi?id=753713#c6)
* In some cases, this setting will be ignored and hardcoded defaults will be used. [[4]](https://bugzilla.gnome.org/show_bug.cgi?id=755953#c17)
**Warning:** Please note that the [acpid](/index.php/Acpid "Acpid") daemon also handles the "power button" and "hibernate button" events. Running both systems at the same time may lead to unexpected behaviour.
Either create the following keyfile:
`/etc/dconf/db/gdm.d/05-power`
```
[org/gnome/settings-daemon/plugins/power]
power-button-action='*action*'
```
and then recompile the GDM database or alternatively log in to the GDM user and execute the following:
```
$ gsettings set org.gnome.settings-daemon.plugins.power power-button-action '*action*'
```
where *action* can be one of `nothing`, `suspend` or `hibernate`.
#### Enabling tap-to-click
Tap-to-click is disabled in GDM (and GNOME) by default, but you can easily enable it with a dconf setting.
**Note:** If you want to do this under X, you have to first set up correct X server access permissions - see [#Configure X server access permission](#Configure_X_server_access_permission).
To directly enable tap-to-click, use:
`# sudo -u gdm gsettings set org.gnome.desktop.peripherals.touchpad tap-to-click true`
If you prefer to do this with a GUI, use:
`# sudo -u gdm dconf-editor`
To check the if it was set correctly, use:
`$ sudo -u gdm gsettings get org.gnome.desktop.peripherals.touchpad tap-to-click`
If you get the error `dconf-WARNING **: failed to commit changes to dconf: Error spawning command line`, make sure dbus is running:
`$ sudo -u gdm dbus-launch gsettings set org.gnome.desktop.peripherals.touchpad tap-to-click true`
#### Disable/Enable Accessibility Menu
To disable or enable the Accessibility Menu, set the following key in dconf editor:
```
# machinectl shell gdm@
# gsettings set org.gnome.desktop.interface toolkit-accessibility false
# exit
```
The menu is disabled when the key is false, enabled when it is true.
### Keyboard layout
The system keyboard layout will be applied to GDM. See [Keyboard configuration in Xorg#Using X configuration files](/index.php/Keyboard_configuration_in_Xorg#Using_X_configuration_files "Keyboard configuration in Xorg").
**Tip:** See [Wikipedia:ISO 3166-1](https://en.wikipedia.org/wiki/ISO_3166-1 "wikipedia:ISO 3166-1") for a list of keymaps.
If a system has multiple users, it is possible to specify a keyboard layout for GDM to use which is different from the system keyboard layout. Firstly, ensure the package [gnome-control-center](https://www.archlinux.org/packages/?name=gnome-control-center) is installed. Then start *gnome-control-center* and navigate to *Region & Language -> Input Sources*. In the header bar, hit the *Login Screen* toggle button and then choose a keyboard layout from the list. Note that the *Login Screen* button will not be visible in the header bar unless multiple users are present on the system [[5]](https://bugzilla.gnome.org/show_bug.cgi?id=741500).
Users of GDM 2.x (legacy GDM) may need to edit `~/.dmrc` as shown below:
`~/.dmrc`
```
[Desktop]
Language=de_DE.UTF-8 # change to your default lang
Layout=de nodeadkeys # change to your keyboard layout
```
### Change the language
The system language will be applied to GDM. If a system has multiple users, it is possible to set a language for GDM different to the system language. In this case, firstly ensure that [gnome-control-center](https://www.archlinux.org/packages/?name=gnome-control-center) is installed. Then, start *gnome-control-center* and choose *Region & Language*. In the header bar, check the *Login Screen* toggle button. Finally, click on *Language* and choose your language from the list. You will be prompted for your root password. Note that the *Login Screen* button will not be visible in the header bar unless multiple users are present on the system [[6]](https://bugzilla.gnome.org/show_bug.cgi?id=741500).
**Tip:** By adding 2 different input languages, logging out then selecting your default language GDM will remember your choice once the second option is removed.
### Users and login
#### Automatic login
To enable automatic login with GDM, add the following to `/etc/gdm/custom.conf` (replace *username* with your own):
`/etc/gdm/custom.conf`
```
# Enable automatic login for user
[daemon]
AutomaticLogin=*username*
AutomaticLoginEnable=True
```
**Tip:** If GDM fails after adding these lines, comment them out from a TTY.
or for an automatic login with a delay:
`/etc/gdm/custom.conf`
```
[daemon]
TimedLoginEnable=true
TimedLogin=*username*
TimedLoginDelay=1
```
You can set the session used for automatic login (replace `gnome-xorg` with desired session):
`/var/lib/AccountsService/users/*username*` `XSession=gnome-xorg`
#### Passwordless login
If you want to bypass the password prompt in GDM then simply add the following line on the first line of `/etc/pam.d/gdm-password`:
```
auth sufficient pam_succeed_if.so user ingroup nopasswdlogin
```
Then, add the group `nopasswdlogin` to your system. See [Groups](/index.php/Groups "Groups") for group descriptions and group management commands.
Now, add your user to the `nopasswdlogin` group and you will only have to click on your username to login.
**Warning:**
* Do **not** do this for a **root** account.
* You won't be able to change your session type at login with GDM anymore. If you want to change your default session type, you will first need to remove your user from the `nopasswdlogin` group.
#### Passwordless shutdown for multiple sessions
GDM uses polkit and logind to gain permissions for shutdown. You can shutdown the system when multiple users are logged in by setting:
`/etc/polkit-1/localauthority.conf.d/org.freedesktop.logind.policy`
```
Shutdown the system when multiple users are logged in
System policy prevents shutting down the system when other users are logged in
yes
yes
```
You can find all available logind options (e.g. reboot-multiple-sessions) [here](http://www.freedesktop.org/wiki/Software/systemd/logind#Security).
#### Enable root login in GDM
It is not advised to login as root, but if necessary you can edit `/etc/pam.d/gdm-password` and add the following line before the line `auth required pam_deny.so`:
`/etc/pam.d/gdm-password`
```
auth sufficient pam_succeed_if.so uid eq 0 quiet
```
The file should look something like this:
`/etc/pam.d/gdm-password`
```
...
auth sufficient pam_succeed_if.so uid eq 0 quiet
auth sufficient pam_succeed_if.so uid >= 1000 quiet
auth required pam_deny.so
...
```
You should be able to login as root after restarting GDM.
#### Hide user from login list
The users for the gdm user list are gathered by [AccountsService](https://www.freedesktop.org/wiki/Software/AccountsService/). It will automatically hide system users (UID < 1000). To hide ordinary users from the login list create or edit a file named after the user to hide in `/var/lib/AccountsService/users/` to contain at least:
`/var/lib/AccountsService/users/`
```
[User]
SystemAccount=true
```
### Setup default monitor settings
Some [desktop environments](/index.php/Desktop_environments "Desktop environments") store display settings in `~/.config/monitors.xml`. *xrandr* commands are then generated on the base of the file content. GDM has a similar file stored in `/var/lib/gdm/.config/monitors.xml`.
If you have your monitors setup as you like (orientation, primary and so on) in `~/.config/monitors.xml` and want GDM to honor those settings:
```
# cp ~/.config/monitors.xml /var/lib/gdm/.config/monitors.xml
```
Changes will take effect on logout. This is necessary because GDM does not respect `xorg.conf`.
**Note:** If you use GDM under Wayland, you must also use a `monitors.xml` that was created under Wayland. See [GNOME bug 748098](https://bugzilla.gnome.org/show_bug.cgi?id=748098) for more info. Alternatively, you can force GDM to [#Use Xorg backend](#Use_Xorg_backend), and use a `monitors.xml` that was created under Xorg.
### Configure X server access permission
You can use the `xhost` command to configure X server access permissions.
For instance, to grant GDM the right to access the X server, use the following command:
`# xhost +SI:localuser:gdm`
## Troubleshooting
### Failure to use proprietary NVIDIA driver
GDM uses the [Wayland](/index.php/Wayland "Wayland") backend by default which conflicts with NVIDIA driver. Turning off the Wayland backend could enable proprietary NVIDIA driver.
### Failure on logout
If GDM starts up properly on boot, but fails after repeated attempts on logout, try adding this line to the daemon section of `/etc/gdm/custom.conf`:
```
GdmXserverTimeout=60
```
### Rootless Xorg
See [Xorg#Rootless Xorg](/index.php/Xorg#Rootless_Xorg "Xorg").
### Use Xorg backend
The [Wayland](/index.php/Wayland "Wayland") backend is used by default and the [Xorg](/index.php/Xorg "Xorg") backend is used only if the Wayland backend cannot be started. As the Wayland backend has been [reported](https://bugzilla.redhat.com/show_bug.cgi?id=1199890) to cause problems for some users, use of the Xorg backend may be necessary. To use the Xorg backend by default, edit the `/etc/gdm/custom.conf` file and uncomment the following line:
```
#WaylandEnable=false
```
### Incomplete removal of gdm
After removing [gdm](https://www.archlinux.org/packages/?name=gdm), [systemd](/index.php/Systemd "Systemd") may report the following:
```
user 'gdm': directory '/var/lib/gdm' does not exist
```
To remove this warning, login as root and delete the primary user "gdm" and then delete the group "gdm":
```
# userdel gdm
# groupdel gdm
```
Verify that gdm is successfully removed via `pwck` and `grpck`. To round it off, you may want to double-check no [unowned files](/index.php/Pacman/Tips_and_tricks#Identify_files_not_owned_by_any_package "Pacman/Tips and tricks") for gdm remain.
### GDM auto-suspend (GNOME 3.28)
GDM uses a separate dconf database to control power management. You can make GDM behave the same way as user sessions by copying the user settings to GDM's dconf database.
```
$ IFS=$'
'; for x in $(sudo -u YOUR_USER gsettings list-recursively org.gnome.settings-daemon.plugins.power); do eval "sudo -u gdm dbus-launch gsettings set $x"; done; unset IFS
```
Or to simply disable auto-suspend (also run the command with `ac` replaced with `battery` to also disable it while running on battery):
```
$ sudo -u gdm dbus-launch gsettings set org.gnome.settings-daemon.plugins.power sleep-inactive-ac-type 'nothing'
```
## See also
* [GDM Reference Manual](https://help.gnome.org/admin/gdm/stable/index.html.en)