wiki/virt/vm/display.md

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---
title: Display
description: How to access a virtual machine's display
published: true
date: 2022-08-24T23:45:25.923Z
tags:
editor: markdown
dateCreated: 2022-07-31T09:22:05.854Z
---
# Display
A virtual display can be attached to a virtual machine, letting a user see the content of it. It is a must-have for non-headless scenario.
## Summary
> *[Official ressource](https://libvirt.org/formatdomain.html#graphical-framebuffers) for `libvirt`-compatible displays, including various XML examples*
>
{.is-info}
* *to-be done. Add table here*.
## Specific displays
### VNC
* *to-be done*
### Spice
* *to-be done*
### SDL
The Simple DirectMedia Layer is a local-only low-latency display.
> *SDL is currently only avalable with virtual machines created using the QEMU/KVM **User Session** mode*
{.is-info}
> *As of now, this method is not compatible with Wayland* {.is-info}
> *Mouse grab does not currently work in SDL*
{.is-warning}
* The display resolution of your guest display should not exceed that of your physical screen.
#### SELinux configuration
By default, SELinux will block access to X Windows Server for the virtualization stack. An exception has to be set.
* Set new rule
```
sudo setsebool -P virt_use_xserver 1
```
* Do some magic trick
```
sudo ausearch -c 'qemu-system-x86' --raw | audit2allow -M my-qemusystemx86
k
```
* And another one
```
sudo semodule -X 300 -i my-qemusystemx86.pp
```
#### XML SDL example
* Example of an XML SDL configuration, with OpenGL enabled. This example requires a 3D-capable graphic card to be attached to the guest computer, such as ``virtio-gpu`` or ``vfio-pci``.
```
<graphics type="sdl" display=":0.0">
<gl enable="yes"/>
</graphics>
```
> *You can identify your display using the following command: `echo $DISPLAY`*
{.is-info}
### D-Bus
> *The D-Bus display is only available since version 7.4.0 of *`libvirt`**
{.is-warning}
[D-Bus](https://www.freedesktop.org/wiki/Software/dbus/) is a Desktop-oriented middleware that can be used to create a display for a virtual machine.
> *[Detailed presentation](https://bootlin.com/pub/conferences/2016/meetup/dbus/josserand-dbus-meetup.pdf) on D-Bus*
{.is-info}
* Export and enable a video backend, add support for OpenGL and peer-to-peer connection:
Does not display at the moment.
SELinux needs to be disabled.
```
<graphics type="dbus"/>
<p2p value="on"/>
<gl enable="yes"/>
</graphics>
```
It will look like that when launched:
```
<graphics type="dbus" address="unix:path=/run/user/1000/libvirt/qemu/run/dbus/8-user-d-bus-dbus.sock">
<gl enable="yes" rendernode="/dev/dri/renderD128"/>
</graphics>
```
* Export and enable an audio backend:
```
<graphics type="dbus">
<audio id="1">
</graphics>
```
### Xephyr
* *to-be done*
### WebRTC
* *to-be done*
### Looking Glass
* *to-be done*
### virtio-wayland
* *to-be done*
### egl-headless
* *to-be done*