X server

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The X.Org server, part of the X.Org releases, is the main component of the X Window system which abstracts the hardware and provides the foundation for most graphical user interfaces, like desktop environments or window managers, and their applications.

Functionality of the X.Org server is handled by Xwayland on systems running the Wayland protocol.

See also
This page provides useful information but the Xorg guide details the installation of Xorg in a more convenient manner. See also Xorg.


Installing xorg-server is much lighter than emerging the entire xorg package, and has all the necessary components to have a fully functional GUI such as plasma for example.

When just updating, check the upgrade sub-article.

USE flags

Portage knows the X USE flag for enabling support for X in other packages (default in all desktop profiles). Make sure this USE flag is added to the USE flag list to ensure X compatibility system wide:

FILE /etc/portage/make.conf


x11-base/xorg-drivers is a meta package to pull in the wanted drivers (note that these driver can be automatically pulled in if the graphics card/drivers info is set in make.conf and using a graphical profile) Issue the command emerge --search xorg-drivers to see if xorg-drivers is already installed prior to emerging.

Follow the links for information how to set up these devices.

It is recommended to issue the --verbose option when emerging xorg-server because xorg-drivers or mesa may be pulled in as dependencies if they are not already installed. Using --verbose will show more information on USE flags and dependencies before package installation. If xorg-drivers and/or the mesa packages are emerged directly (IE without the --one-shot option) they will be recorded in the world file and could cause future package upgrade conflicts when Portage is upgrading dependencies. It is a best practice to allow them to be merged into the system as dependencies by setting USE flags or using a graphical profile.


media-libs/mesa (see Wikipedia) is a graphic library that provides a generic OpenGL implementation. Mesa may already be automatically pulled in by graphics card/driver settings in make.conf and if a graphical profile is set. Issue the command emerge --search mesa to see if mesa is already installed prior to emerging.


Now install x11-base/xorg-server.

USE flags for x11-base/xorg-server X.Org X servers

debug Enable extra debug codepaths, like asserts and extra output. If you want to get meaningful backtraces see https://wiki.gentoo.org/wiki/Project:Quality_Assurance/Backtraces
elogind Use elogind to get control over framebuffer when running as regular user
minimal Install a very minimal build (disables, for example, plugins, fonts, most drivers, non-critical features)
selinux !!internal use only!! Security Enhanced Linux support, this must be set by the selinux profile or breakage will occur
suid Enable setuid root program(s)
systemd Enable use of systemd-specific libraries and features like socket activation or session tracking
test Enable dependencies and/or preparations necessary to run tests (usually controlled by FEATURES=test but can be toggled independently)
udev Enable virtual/udev integration (device discovery, power and storage device support, etc)
unwind Enable libunwind usage for backtraces
xcsecurity Build Security extension
xephyr Build the Xephyr server
xnest Build the Xnest server
xorg Build the Xorg X server (HIGHLY RECOMMENDED)
xvfb Build the Xvfb server

root #emerge --ask x11-base/xorg-server

x11 overlay

The Gentoo X11 team maintains the x11 overlay. It contains main and 'live' revisions of X.Org versions in preparation to be moved into gentoo.git , the primary Gentoo ebuild repository. Use eselect repository to setup the repository.



If the acl USE flag is enabled globally and elogind is being used (default for desktop profiles) permissions to video cards will be handled automatically. It is possible to check the permissions using getfacl:

user $getfacl /dev/dri/card0 | grep larry

A broader solution is to add the user(s) needing access the video card to the video group:

root #gpasswd -a larry video

Note that users will be able to run X without permission to the DRI subsystem, but hardware acceleration will be disabled.


The X server is designed to work out-of-the-box, with no need to manually edit Xorg's configuration files. It should detect and configure devices such as displays, keyboards, and mice.

However, the main configuration file of the X server is the xorg.conf.

Boot service

Usually the X server is started by starting a display manager automatically on boot.

See also

  • Non root Xorg — describes how an unprivileged user can run Xorg without using suid.
  • Xorg — an open source implementation of the X server.
  • Xorg/Guide — explains what Xorg is, how to install it, and the various configuration options.
  • XrandrX protocol extension and its CLI tool xrandr are used to manage screen resolutions, rotation and screens with multiply displays in X