docker-nvidia-glx-desktop

KDE Plasma Desktop container designed for Kubernetes, supporting OpenGL EGL and GLX, Vulkan, and Wine/Proton for NVIDIA GPUs through WebRTC and HTML5, providing an open-source remote cloud/HPC graphics or game streaming platform. Spawns its own fully isolated X.Org X11 Server instead of using the host X Server, not requiring /tmp/.X11-unix host sockets or host configuration.

Use docker-nvidia-egl-desktop for a KDE Plasma Desktop container which directly accesses NVIDIA (and unofficially Intel and AMD) GPUs without using an X.Org X11 Server, supports sharing one GPU with many containers, supports Apptainer/Singularity, and automatically falling back to software acceleration in the absence of GPUs (but with lower graphics performance).

Please read Troubleshooting first, then use Discord or GitHub Discussions for support questions. Please only use Issues for technical inquiries or bug reports.

Usage

Container startup may take some time at first launch as it could automatically install NVIDIA driver libraries compatible with the host.

For Windows applications or games, Wine, Winetricks, Lutris, Heroic Launcher, PlayOnLinux, and q4wine are bundled by default. Comment out the section where it is installed within Dockerfile if the user wants containers without Wine.

The container requires host NVIDIA GPU driver versions of at least 450.80.02 and preferably 470.42.01 (the latest minor version in each major version), with the NVIDIA Container Toolkit to be also configured on the host for allocating GPUs. The latest minor versions (xx in 000.xx.00) are strongly encouraged. All Maxwell or later generation GPUs in the consumer, professional, or datacenter lineups should not have significant issues running this container, although the Selkies-GStreamer high-performance NVENC backend may not be available. Kepler GPUs are untested and likely does not support the NVENC backend, but can be mostly functional using fallback software acceleration.

The high-performance NVENC backend for the Selkies-GStreamer WebRTC interface is only supported in GPUs listed as supporting H.264 (AVCHD) under the NVENC - Encoding section of NVIDIA's Video Encode and Decode GPU Support Matrix. If your GPU is not listed as supporting H.264 (AVCHD), add the environment variable SELKIES_ENCODER to values including x264enc, vp8enc, or vp9enc in your container configuration for falling back to software acceleration, which also has a very good performance depending on your CPU.

There are two web interfaces that may be chosen in this container, the first being the default Selkies-GStreamer WebRTC HTML5 web interface (requires a TURN server or host networking for best performance), and the second being the fallback KasmVNC WebSocket HTML5 web interface. While the KasmVNC interface does not support audio forwarding, it can be useful for troubleshooting the Selkies-GStreamer WebRTC interface or using this container in constrained environments.

The KasmVNC interface can be enabled in place of Selkies-GStreamer by setting KASMVNC_ENABLE to true. KASMVNC_THREADS sets the number of threads KasmVNC should use for frame encoding, defaulting to all threads if not set. When using the KasmVNC interface, environment variables SELKIES_ENABLE_BASIC_AUTH, SELKIES_BASIC_AUTH_USER, SELKIES_BASIC_AUTH_PASSWORD, SELKIES_ENABLE_RESIZE, SELKIES_ENABLE_HTTPS, SELKIES_HTTPS_CERT, and SELKIES_HTTPS_KEY, used with Selkies-GStreamer, are also inherited. As with the Selkies-GStreamer WebRTC interface, the KasmVNC interface username and password will also be set to the environment variables SELKIES_BASIC_AUTH_USER and SELKIES_BASIC_AUTH_PASSWORD, also using ubuntu and the environment variable PASSWD by default if not set.

Running with Docker

1. Run the container with Docker, Podman, or other NVIDIA-supported container runtimes (NVIDIA Container Toolkit required):

docker run --pull=always --name xgl -it -d --gpus 1 --tmpfs /dev/shm:rw -e TZ=UTC -e DISPLAY_SIZEW=1920 -e DISPLAY_SIZEH=1080 -e DISPLAY_REFRESH=60 -e DISPLAY_DPI=96 -e DISPLAY_CDEPTH=24 -e PASSWD=mypasswd -e SELKIES_ENCODER=nvh264enc -e SELKIES_VIDEO_BITRATE=8000 -e SELKIES_FRAMERATE=60 -e SELKIES_AUDIO_BITRATE=128000 -e SELKIES_BASIC_AUTH_PASSWORD=mypasswd -p 8080:8080 ghcr.io/selkies-project/nvidia-glx-desktop:latest

Alternatively, use Docker Compose by editing the docker-compose.yml file:

# Start the container from the path containing docker-compose.yml
docker compose up -d
# Stop the container
docker compose down

If the Selkies-GStreamer WebRTC HTML5 interface does not connect or is extremely slow, read Step 3 and the WebRTC and Firewall Issues section very carefully.

NOTE: The container tags available are latest and 24.04 for Ubuntu 24.04, 22.04 for Ubuntu 22.04, and 20.04 for Ubuntu 20.04. Persistent container tags are available in the form 24.04-20210101010101. Replace all instances of mypasswd with your desired password. SELKIES_BASIC_AUTH_PASSWORD will default to PASSWD if unspecified. The container must NOT be run in privileged mode.

Change SELKIES_ENCODER to x264enc, vp8enc, or vp9enc when using the Selkies-GStreamer interface if your GPU does not support H.264 (AVCHD) under the NVENC - Encoding section in NVIDIA's Video Encode and Decode GPU Support Matrix.

2. Connect to the web server with a browser on port 8080. You may also separately configure a reverse proxy to this port for external connectivity.

The default username is ubuntu for both the web authentication prompt and the container Linux username. The environment variable PASSWD (defaulting to mypasswd) is the password for the container Linux user account, and SELKIES_BASIC_AUTH_PASSWORD is the password for the HTML5 interface authentication prompt. If SELKIES_ENABLE_BASIC_AUTH is set to true for Selkies-GStreamer but SELKIES_BASIC_AUTH_PASSWORD is unspecified, the HTML5 interface password will default to PASSWD.

NOTE: Only one web browser can be connected at a time with the Selkies-GStreamer WebRTC interface. If the signaling connection works, but the WebRTC connection fails, read Step 3 and the WebRTC and Firewall Issues section.

Additional configurations and environment variables for the Selkies-GStreamer WebRTC HTML5 interface are listed in lines that start with parser.add_argument within the Selkies-GStreamer Main Script or selkies-gstreamer --help.

3. (Not Applicable for KasmVNC) Read carefully if the Selkies-GStreamer WebRTC HTML5 interface does not connect or is extremely slow.

A TURN server is required because you are self-hosting WebRTC, unlike commercial services using WebRTC.

Choose whether to use host networking, an internal TURN server, or an external TURN server.

• Internal TURN Server:

Open Section

There is an internal TURN server inside the container that may be used when an external TURN server or host networking is not available.

Add environment variables -e SELKIES_TURN_PROTOCOL=udp -e SELKIES_TURN_PORT=3478 -e TURN_MIN_PORT=65534 -e TURN_MAX_PORT=65535 (change the ports accordingly) with the docker run command (or uncomment the relevant docker-compose.yml sections), where the SELKIES_TURN_PORT should not be used by any other host process or container, and the TURN_MIN_PORT/TURN_MAX_PORT port range has to contain at least two ports also not used by any other host process or container.

Then, open the ports with the docker run arguments -p 8080:8080 -p 3478:3478 -p 3478:3478/udp -p 65534-65535:65534-65535 -p 65534-65535:65534-65535/udp (or uncomment the relevant docker-compose.yml sections) in addition to the web server port.

All these ports must be exposed to the internet if you need access over the internet. If you need use TURN within a local network, add -e SELKIES_TURN_HOST=[YOUR_INTERNAL_IP] with YOUR_INTERNAL_IP to the internal hostname or IP of the local network.

If UDP cannot be used, at the cost of higher latency and lower performance, omit the ports containing /udp and use the environment variable -e SELKIES_TURN_PROTOCOL=tcp.

• Host Networking:

Open Section

The Selkies-GStreamer WebRTC HTML5 interface will likely just start working if you open UDP and TCP ports 49152–65535 in your host server network and add --network host to the above docker run command, or network_mode: 'host' in docker-compose.yml. When deploying multiple containers, you must also pass a new DISPLAY environment variable such as -e DISPLAY=:22, that is not used with any other X11 server or container in the same host, into the container.

However, host networking may be restricted or not be desired because of security reasons. If not available, check if the container starts working after omitting --network host.

• External TURN Server:

Open Section

If having no TURN server does not work, you need an external TURN server. Read the WebRTC and Firewall Issues section and add the environment variables -e SELKIES_TURN_HOST=, -e SELKIES_TURN_PORT=, and pick one of -e SELKIES_TURN_SHARED_SECRET= or both -e SELKIES_TURN_USERNAME= and -e SELKIES_TURN_PASSWORD= environment variables to the docker run command based on your authentication method.

Running with Kubernetes

1. Create the Kubernetes Secret with your authentication password (change keys and values as adequate):

kubectl create secret generic my-pass --from-literal=my-pass=YOUR_PASSWORD

NOTE: Replace YOUR_PASSWORD with your desired password, and change the name my-pass to your preferred name of the Kubernetes secret with the xgl.yml file changed accordingly as well. It is possible to skip the first step and directly provide the password with value: in xgl.yml, but this exposes the password in plain text.

2. Create the pod after editing the xgl.yml file to your needs, explanations are available in the file:

kubectl create -f xgl.yml

If the Selkies-GStreamer WebRTC HTML5 interface does not connect or is extremely slow, read Step 4 and the WebRTC and Firewall Issues section very carefully.

NOTE: The container tags available are latest and 24.04 for Ubuntu 24.04, 22.04 for Ubuntu 22.04, and 20.04 for Ubuntu 20.04. Persistent container tags are available in the form 24.04-20210101010101. SELKIES_BASIC_AUTH_PASSWORD will default to PASSWD if unspecified. The container must NOT be run in privileged mode.

Change SELKIES_ENCODER to x264enc, vp8enc, or vp9enc when using the Selkies-GStreamer interface if your GPU does not support H.264 (AVCHD) under the NVENC - Encoding section in NVIDIA's Video Encode and Decode GPU Support Matrix.

3. Connect to the web server spawned at port 8080. You may configure the ingress endpoint or reverse proxy that your Kubernetes cluster provides to this port for external connectivity.

The default username is ubuntu for both the web authentication prompt and the container Linux username. The environment variable PASSWD (defaulting to mypasswd) is the password for the container Linux user account, and SELKIES_BASIC_AUTH_PASSWORD is the password for the HTML5 interface authentication prompt. If SELKIES_ENABLE_BASIC_AUTH is set to true for Selkies-GStreamer but SELKIES_BASIC_AUTH_PASSWORD is unspecified, the HTML5 interface password will default to PASSWD.

NOTE: Only one web browser can be connected at a time with the Selkies-GStreamer WebRTC interface. If the signaling connection works, but the WebRTC connection fails, read Step 4 and the WebRTC and Firewall Issues section.

Additional configurations and environment variables for the Selkies-GStreamer WebRTC HTML5 interface are listed in lines that start with parser.add_argument within the Selkies-GStreamer Main Script or selkies-gstreamer --help.

4. (Not Applicable for KasmVNC) Read carefully if the Selkies-GStreamer WebRTC HTML5 interface does not connect or is extremely slow.

A TURN server is required because you are self-hosting WebRTC, unlike commercial services using WebRTC.

Choose whether to use host networking, an internal TURN server, or an external TURN server.

• Internal TURN Server:

Open Section

There is an internal TURN server inside the container that may be used when an external TURN server or host networking is not available.

Uncomment the relevant environment variables SELKIES_TURN_PROTOCOL=udp, SELKIES_TURN_PORT=3478, TURN_MIN_PORT=65534, TURN_MAX_PORT=65535 (change the ports accordingly) within xgl.yml (within name: and value:), where the SELKIES_TURN_PORT should not be used by any other host process or container, and the TURN_MIN_PORT/TURN_MAX_PORT port range has to contain at least two ports also not used by any other host process or container. Then, open all of these ports in the Kubernetes configuration ports: section in addition to the web server port.

All these ports must be exposed to the internet if you need access over the internet. If you need use TURN within a local network, add the environment variable SELKIES_TURN_HOST=[YOUR_INTERNAL_IP] (within name: and value:) with YOUR_INTERNAL_IP to the internal hostname or IP of the local network.

If UDP cannot be used, at the cost of higher latency and lower performance, omit the ports containing /udp and use the environment variable SELKIES_TURN_PROTOCOL=tcp (within name: and value:).

• Host Networking:

Open Section

Otherwise, the Selkies-GStreamer WebRTC HTML5 interface will likely just start working if you open UDP and TCP ports 49152–65535 in your host server network and uncomment hostNetwork: true in xgl.yml. When deploying multiple containers with hostNetwork: true, you must also pass a new DISPLAY environment variable such as the value :22, that is not used with any other X11 server or container in the same host, into the container.

However, host networking may be restricted or not be desired because of security reasons. If not available, check if the container starts working after commenting out hostNetwork: true.

• External TURN Server:

Open Section

If having no TURN server does not work, you need an external TURN server. Read the WebRTC and Firewall Issues section and fill in the environment variables SELKIES_TURN_HOST and SELKIES_TURN_PORT, then pick one of SELKIES_TURN_SHARED_SECRET or both SELKIES_TURN_USERNAME and SELKIES_TURN_PASSWORD environment variables, based on your authentication method.

WebRTC and Firewall Issues

Note that this section is only required for the Selkies-GStreamer WebRTC HTML5 interface.

In most cases when either of your server or client has a permissive firewall, the default Google STUN server configuration will work without additional configuration. However, when connecting from networks that cannot be traversed with STUN, a TURN server is required.

Read the last steps of each Docker/Kubernetes instruction to use an internal TURN server. Alternatively, read the below sections.

For an easy fix to when the signaling connection works, but the WebRTC connection fails, open UDP and TCP ports 49152–65535 in your host server network (or use Full Cone NAT in your network router/infrastructure settings), then add the option --network host to your Docker command (or network_mode: 'host' in docker-compose.yml), or uncomment hostNetwork: true in your xgl.yml file when using Kubernetes (note that your cluster may have not allowed this, resulting in an error). This exposes your container to the host network, which disables network isolation.

When deploying multiple containers with host networking, you must also pass a new DISPLAY environment variable such as -e DISPLAY=:22, that is not used with any other X11 server or container in the same host, into the container.

If this does not fix the connection issue (normally when the host is behind another additional firewall) or you cannot use this fix for security or technical reasons, read the below text to set up an external TURN server.

Deploying a TURN server

Read the instructions from Selkies-GStreamer if want to deploy an external TURN server or use a public TURN server instance. Read the last steps of each Docker/Kubernetes instruction to use an internal TURN server instead.

Configuring with Docker

More information is available in the Selkies-GStreamer documentation.

With Docker (or Podman), use the -e option to add the SELKIES_TURN_HOST, SELKIES_TURN_PORT environment variables. This is the hostname or IP and the port of the TURN server (3478 in most cases).

You may set SELKIES_TURN_PROTOCOL to tcp if you are only able to open TCP ports for the coTURN container to the internet, or if the UDP protocol is blocked or throttled in your client network. You may also set SELKIES_TURN_TLS to true with the -e option if TURN over TLS/DTLS was properly configured with valid TLS certificates.

You also require to provide either only the environment variable SELKIES_TURN_SHARED_SECRET for time-limited shared secret TURN authentication, or both the environment variables SELKIES_TURN_USERNAME and SELKIES_TURN_PASSWORD for legacy long-term TURN authentication, depending on your TURN server configuration. Provide just one of these authentication methods, not both.

If there is a TURN REST API server, provide the environment variable SELKIES_TURN_REST_URI but not any other authentication credentials to the TURN REST URI within this infrastructure. If there is a shared TURN server within an infrastructure, consider reading the TURN REST API documentation or provide the link to your infrastructure administrator to deploy a TURN REST API server.

Configuring with Kubernetes

More information is available in the Selkies-GStreamer documentation.

Your TURN server will use only one out of three ways to authenticate the client, so only provide one type of authentication method. The time-limited shared secret TURN authentication only requires the Base64 encoded SELKIES_TURN_SHARED_SECRET. The legacy long-term TURN authentication requires both SELKIES_TURN_USERNAME and SELKIES_TURN_PASSWORD credentials. The TURN REST API method only requires the SELKIES_TURN_REST_URI URI.

TURN REST API

If there is a shared TURN server within an infrastructure, consider reading the TURN REST API documentation or provide the link to your infrastructure administrator to deploy a TURN REST API server.

Open Section

Then, uncomment the lines in the xgl.yml file related to TURN server usage, updating the SELKIES_TURN_REST_URI environment variable as needed:

- name: SELKIES_TURN_REST_URI
  value: "https://turn-rest.myinfrastructure.io:8443/myturnrest"
- name: SELKIES_TURN_PROTOCOL
  value: "udp"
- name: SELKIES_TURN_TLS
  value: "false"

Time-limited shared secret authentication

Open Section

1. Create a secret containing the TURN shared secret:

kubectl create secret generic turn-shared-secret --from-literal=turn-shared-secret=MY_SELKIES_TURN_SHARED_SECRET

NOTE: Replace MY_SELKIES_TURN_SHARED_SECRET with the shared secret of the TURN server, then changing the name turn-shared-secret to your preferred name of the Kubernetes secret, with the xgl.yml file also being changed accordingly.

2. Uncomment the lines in the xgl.yml file related to TURN server usage, updating the SELKIES_TURN_HOST and SELKIES_TURN_PORT environment variables as needed:

- name: SELKIES_TURN_HOST
  value: "turn.example.com"
- name: SELKIES_TURN_PORT
  value: "3478"
- name: SELKIES_TURN_SHARED_SECRET
  valueFrom:
    secretKeyRef:
      name: turn-shared-secret
      key: turn-shared-secret
- name: SELKIES_TURN_PROTOCOL
  value: "udp"
- name: SELKIES_TURN_TLS
  value: "false"

NOTE: It is possible to skip the first step and directly provide the shared secret with value:, but this exposes the shared secret in plain text. Set SELKIES_TURN_PROTOCOL to tcp if you were able to only open TCP ports while creating your own coTURN Deployment/DaemonSet, or if your client network throttles or blocks the UDP protocol at the cost of higher latency and lower performance.

Legacy long-term authentication

Open Section

1. Create a secret containing the TURN password:

kubectl create secret generic turn-password --from-literal=turn-password=MY_SELKIES_TURN_PASSWORD

NOTE: Replace MY_SELKIES_TURN_PASSWORD with the password of the TURN server, then changing the name turn-password to your preferred name of the Kubernetes secret, with the xgl.yml file also being changed accordingly.

2. Uncomment the lines in the xgl.yml file related to TURN server usage, updating the SELKIES_TURN_HOST, SELKIES_TURN_PORT, and SELKIES_TURN_USERNAME environment variables as needed:

- name: SELKIES_TURN_HOST
  value: "turn.example.com"
- name: SELKIES_TURN_PORT
  value: "3478"
- name: SELKIES_TURN_USERNAME
  value: "username"
- name: SELKIES_TURN_PASSWORD
  valueFrom:
    secretKeyRef:
      name: turn-password
      key: turn-password
- name: SELKIES_TURN_PROTOCOL
  value: "udp"
- name: SELKIES_TURN_TLS
  value: "false"

NOTE: It is possible to skip the first step and directly provide the TURN password with value:, but this exposes the TURN password in plain text. Set SELKIES_TURN_PROTOCOL to tcp if you were able to only open TCP ports while creating your own coTURN Deployment/DaemonSet, or if your client network throttles or blocks the UDP protocol at the cost of higher latency and lower performance.

Troubleshooting

I have an issue related to the Selkies-GStreamer WebRTC HTML5 interface.

Link

I want to use the keyboard layout of my own language.

Open Answer

Run Input Method: Configure Input Method from the start menu, uncheck Only Show Current Language, search and add from available input methods (Hangul, Mozc, Pinyin, and others) by moving to the right, then use Ctrl + Space to switch between the input methods. Raise an issue if you need more layouts.

The container does not work.

Open Answer

Check that the NVIDIA Container Toolkit is properly configured in the host. Next, check that your host NVIDIA GPU driver is not the nvidia-headless variant, which lacks the required display and graphics capabilities for this container.

After that, check the environment variable NVIDIA_DRIVER_CAPABILITIES after starting a shell interface inside the container. NVIDIA_DRIVER_CAPABILITIES should be set to all, or include a comma-separated list of compute (requirement for CUDA and OpenCL, or for the Selkies-GStreamer WebRTC remote desktop interface), utility (requirement for nvidia-smi and NVML), graphics (requirement for OpenGL and part of the requirement for Vulkan), video (required for encoding or decoding videos using NVIDIA GPUs, or for the Selkies-GStreamer WebRTC remote desktop interface), display (the other requirement for Vulkan), and optionally compat32 if you use Wine or 32-bit graphics applications.

Moreover, if you are using custom configurations, check if your shared memory path /dev/shm has sufficient capacity, where expanding the capacity is done by adding --tmpfs /dev/shm:rw to your Docker command or adding the below lines to your Kubernetes configuration file.

spec:
  template:
    spec:
      containers:
        volumeMounts:
        - mountPath: /dev/shm
          name: dshm
      volumes:
      - name: dshm
        emptyDir:
          medium: Memory

If you checked everything here, scroll down.

I want to use systemd, polkit, FUSE mounts, or sandboxed (containerized) application distribution systems like Flatpak, Snapcraft (snap), AppImage, and etc.

Open Answer

Use the option --appimage-extract-and-run or --appimage-extract with your AppImage to run them in a container. Alternatively, set export APPIMAGE_EXTRACT_AND_RUN=1 to your current shell.

Do not use systemd, polkit, FUSE mounts, or sandboxed application distribution systems with containers. You can use them if you add unsafe capabilities to your containers, but it will break the isolation of the containers. This is especially bad if you are using Kubernetes. There will likely be an alternative way to install the applications instead of Snapcraft (snap) or Flatpak, including Personal Package Archives. For some applications, especially those using the Electron framework, there will be options to disable sandboxing when running or options to extract files before running.

I want to share one GPU with multiple containers to run GUI workloads.

Open Answer

Note that because of restrictions from Xorg, it is not possible to share one GPU to multiple Xorg servers running in different containers. Use docker-nvidia-egl-desktop if you intend to do this.

The container does not work if an existing GUI, desktop environment, or X server is running in the host outside the container. / I want to use this container in --privileged mode or with --cap-add and do not want other containers to interfere.

Open Answer

In order to use an X server on the host for your monitor with one GPU, and provision the other GPUs to the containers, you must change your /etc/X11/xorg.conf configuration of the host, outside the container.

First, use nvidia-xconfig --no-probe-all-gpus --busid=$BUS_ID --only-one-x-screen to generate /etc/X11/xorg.conf where BUS_ID is generated with the below script. Set GPU_SELECT to the ID (from nvidia-smi) of the specific GPU you want to provision.

HEX_ID=$(nvidia-smi --query-gpu=pci.bus_id --id="$GPU_SELECT" --format=csv,noheader | head -n1)
IFS=":." ARR_ID=($HEX_ID)
unset IFS
BUS_ID=PCI:$((16#${ARR_ID[1]})):$((16#${ARR_ID[2]})):$((16#${ARR_ID[3]}))

Then, edit the /etc/X11/xorg.conf file of your host outside the container and add the below snippet to the end of the file. If you want to use containers in --privileged mode or with --cap-add, add the snippet to the /etc/X11/xorg.conf files of all other containers running an Xorg server as well (already added for Selkies). The exact file location may vary if not using the NVIDIA graphics driver.

Section "ServerFlags"
    Option "AutoAddGPU" "false"
EndSection

Reference

If you restart your OS or the Xorg server, you will now be able to use one GPU for your host X server and your real monitor, and use the other GPUs for the containers.

Then, you must avoid the GPU of which you are using for your host X server. Use docker --gpus '"device=1,2"' to provision GPUs with (for example) device IDs 1 and 2 to the container, avoiding the GPU with the ID of 0 that is used by the host X server, if you set GPU_SELECT to the ID of 0. Note that --gpus 1 means any single GPU, not the GPU device ID of 1.

Vulkan does not work.

Open Answer

Make sure that the NVIDIA_DRIVER_CAPABILITIES environment variable is set to all, or includes both graphics and display. The display capability is especially crucial to Vulkan, but the container does start without noticeable issues other than Vulkan without display, despite its name.

The container does not work if I set the resolution above 1920 x 1200 or 2560 x 1600 in 60 hz.

Upgrade to the latest minor version of the NVIDIA driver major version 550 or higher. The answer contains legacy information for people who cannot upgrade.

Open Answer

If your GPU is a consumer or professional GPU, change the VIDEO_PORT environment variable from DFP to DP-0 if DP-0 is empty, or any empty DP-* port. Set VIDEO_PORT to where your monitor is connected if you want to show the remote desktop in a real monitor. If your GPU is a Datacenter (Tesla) GPU, keep the VIDEO_PORT environment variable to DFP, and your maximum resolution is at 2560 x 1600. To go above this restriction, you may set VIDEO_PORT to none, but you must use borderless window instead of fullscreen, and this may lead to quite a lot of applications not starting, showing errors related to XRANDR or RANDR.

The container simulates the GPU to become plugged into a physical DVI-D/HDMI/DisplayPort digital video interface in consumer and professional GPUs with the ConnectedMonitor NVIDIA driver option. The container uses virtualized DVI-D ports for this purpose in Datacenter (Tesla) GPUs.

The ports to be used should only be connected with an actual monitor if the user wants the remote desktop screen to be shown on that monitor. If you want to show the remote desktop screen spawned by the container in a physical monitor, connect the monitor and set VIDEO_PORT to the the video interface identifier that is connected to the monitor. If not, avoid the video interface identifier that is connected to the monitor.

VIDEO_PORT identifiers and their connection states can be obtained by typing xrandr -q when the DISPLAY environment variable is set to the number of the spawned X server display (for example :0). As an alternative, you may set VIDEO_PORT to none (which effectively sets --use-display-device=None), but you must use borderless window instead of fullscreen, and this may lead to quite a lot of applications not starting because the RANDR extension is not available in the X server.

NOTE: Do not start two or more X servers for a single GPU. Use a separate GPU (or use Xvfb/Xdummy/Xvnc without hardware acceleration to use no GPUs at all) if you need a host X server unaffiliated with containers, and do not make the GPU available to the container runtime.

Since this container simulates the GPU being virtually plugged into a physical monitor while it actually does not, make sure the resolutions specified with the environment variables DISPLAY_SIZEW and DISPLAY_SIZEH are within the maximum size supported by the GPU. The environment variable VIDEO_PORT can override which video port is used (defaults to DFP, the first interface detected in the driver). Therefore, specifying VIDEO_PORT to an unplugged DisplayPort (for example numbered like DP-0, DP-1, and so on) is recommended for resolutions above 1920 x 1200 at 60 hz, because some driver restrictions are applied when the default is set to an unplugged physical DVI-D or HDMI port. The maximum size that should work in all cases is 1920 x 1200 at 60 hz, mainly for when the default VIDEO_PORT identifier DFP is not set to DisplayPort. The screen sizes over 1920 x 1200 at 60 hz but under the maximum supported display size specified for each port (supported by GPU specifications) will be possible if the port is set to DisplayPort (both physically connected or disconnected), or when a physical monitor or dummy plug to any other type of display ports (including DVI-D and HDMI) has been physically connected. If all GPUs in the cluster have at least one DisplayPort and they are not physically connected to any monitors, simply setting VIDEO_PORT to DP-0 is recommended (but this is not set as default because of legacy GPU compatibility reasons).

Datacenter (Tesla) GPUs seem to only support resolutions of up to around 2560 x 1600 at 60 hz (VIDEO_PORT must be kept to DFP instead of changing to DP-0 or other DisplayPort identifiers). The K40 (Kepler) GPU did not support RandR (required for some graphical applications using SDL and other graphical frameworks). Other Kepler generation Datacenter GPUs (maybe except the GRID K1 and K2 GPUs with vGPU capabilities) are also unlikely to support RandR, thus Datacenter GPU RandR support probably starts from Maxwell. Other tested Datacenter GPUs (V100, T4, A40, A100) support all graphical applications that consumer GPUs support. However, the performances were not better than consumer GPUs that usually cost a fraction of Datacenter GPUs, and the maximum supported resolutions were even lower.

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This project has been developed and is supported in part by the National Research Platform (NRP) and the Cognitive Hardware and Software Ecosystem Community Infrastructure (CHASE-CI) at the University of California, San Diego, by funding from the National Science Foundation (NSF), with awards #1730158, #1540112, #1541349, #1826967, #2138811, #2112167, #2100237, and #2120019, as well as additional funding from community partners, infrastructure utilization from the Open Science Grid Consortium, supported by the National Science Foundation (NSF) awards #1836650 and #2030508, and infrastructure utilization from the Chameleon testbed, supported by the National Science Foundation (NSF) awards #1419152, #1743354, and #2027170. This project has also been funded by the Seok-San Yonsei Medical Scientist Training Program (MSTP) Song Yong-Sang Scholarship, College of Medicine, Yonsei University, the MD-PhD/Medical Scientist Training Program (MSTP) through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea, and the Student Research Bursary of Song-dang Institute for Cancer Research, College of Medicine, Yonsei University.