Docker - Display GUI

If you are using docker and would like to display the GUI applications from within the docker, please follow the instructions below.

Step 1

Create a container with the following command A normal display

# Start the docker container
docker run \
    -d \
    -ti \
    --net=host \
    -v $(pwd):/home \
    --name u16_opencv \
    --cap-add=SYS_PTRACE \
    --env="DISPLAY" \
    -v /tmp/.X11-unix:/tmp/.X11-unix:rw \
    --privileged \
    -v /usr/lib/nvidia-410:/usr/lib/nvidia-410 \
    -v /usr/lib32/nvidia-410:/usr/lib32/nvidia-410 \
    --device /dev/dri \
    ubuntu:16.04

Display with OpenGL

# Start the docker container
docker run \
    -d \
    -ti \
    --net=host \
    -v $(pwd):/home \
    --name u16_opencv \
    --cap-add=SYS_PTRACE \
    --env="DISPLAY" \
    -v /tmp/.X11-unix:/tmp/.X11-unix:rw \
    --runtime=nvidia \
    -e XAUTHORITY \
    -e NVIDIA_DRIVER_CAPABILITIES=all \
    ubuntu:16.04

Explanation

Attribute	Explanation
run	Run docker container.
-d	Detached mode: run the container in the background and print the new container ID.
-ti	Terminal Interactive (Usually use together, also -it).
--net=host	Use the host's network stack inside the container.
-v	Create a bind mount. If you specify, -v /HOST-DIR:/CONTAINER-DIR, Docker bind mounts /HOST-DIR in the host to /CONTAINER-DIR in the Docker container.
--name u15_opencv	Set the name of the container as u16_opencv
--cap-add=SYS_PTRACE	Add Linux capabilities. Learn more
--env="DISPLAY"	Set the DISPLAY variable in env to be the same as the machine.
-v /tmp/.X11-unix:/tmp/.X11-unix:rw	Let Docker container find X server. (Very important)
ubuntu:16.04	Select container ubuntu with tag as 16.04

Step 2

Connecting to the Docker Container

# Connect to docker container
docker exec -ti u16_opencv bash

Explanation

Attribute	Explanation
exec	exec is for running a command inside an already running container. Hence it is extremely useful for debugging conatiners.
-t	Allocate a pseudo-tty.
-i	Keep STDIN open even if not attached.
u16_opencv	Container name.
bash	Run bash, or can also use /bin/bash.

Step 3

Once connected and inside of the docker container, you may update it and install nautilus.

# Run these commands in the docker container
apt-get update
apt-get upgrade
apt-get install nautilus

Explanation

Installing nautilus is just to test out the GUI status. If you wish you may also install visual studio code.

Step 4

Add a user inside the docker container. Most probably when you start your docker container it is using root and some application cannot start when you are root.

# Add the user bruce, you may skip the details with `enter`
# adduser bruce --disabled-password --uid=3000
adduser bruce --uid=3000
# Use user bruce
su bruce

Explanation

Command	Explanation
adduser	Adding a new user inside docker container. Set the user id as 3000 and disable the password.
su bruce	Use user bruce.

If you do not do this, you may recieve this error. You are trying to start vscode as a super user which is not recommended. If you really want to, you must specify an alternate user data directory using the --user-data-dir argument.

Step 5

Now allow docker using local host to connect to X server.

# Run this command in any local terminal
xhost +local:docker

Explanation

This let xhost allow local user call docker to display GUI.

Finally, launch your GUI application

# Run nautilus and display current directory
nautilus .

Reference

• Understanding host X link
• Understanding --cap-add link
• Difference between exec and exec -ti link
• Start a GUI-Application as root in a Ubuntu Container link
• Displaying with nvidia drivers link
• Docker example that runs nvidia drivers link
• Docker example 2 that runs nvidia dirvers link
• https://github.com/Intel-Media-SDK/MediaSDK/wiki/Running-on-GPU-under-docker
• https://answers.ros.org/question/301056/ros2-rviz-in-docker-container/