Docker Study Notes

System

• CPU: AMD Ryzen 9 5900x
• RAM: 64GB
• GPU: AMD 6800XT
• OS: Ubuntu 20.04
• Kernel Version: 5.13.0-39-generic
• Docker: Docker version 20.10.13, build a224086

Setup Docker Environment

• Install the docker from Docker website (DO not use the install from package manager)
  curl -fsSL https://get.docker.com -o get-docker.sh
sh get-docker.sh

• Option want to use Docker as non-root user:

  sudo usermod -a -G docker $USER

• Install Docker compose
  DOCKER_CONFIG=${DOCKER_CONFIG:-$HOME/.docker}

  mkdir -p $DOCKER_CONFIG/cli-plugins

  Check the docker compose version from the docker github page
  Choose the compose version as you preferred

  curl -SL https://github.com/docker/compose/releases/download/v2.3.3/docker-compose-linux-x86_64 -o $DOCKER_CONFIG/cli-plugins/docker-compose

  chmod +x $DOCKER_CONFIG/cli-plugins/docker-compose

• After the docker environment is set use the following command to check the docker information
  docker version

  docker info

• Docker command line structure
  docker <management_command> <execution_subcommand

Notes

Image and container difference
images: application we want to run

container is an instance of that image running as a process
multiple containers can of the same image

Start Building the container

• Docker container with desktop environment
  
  This is a sample docker container: ubuntu20:04 xrdp xfce-desktop

  • To build the container for more details check docker document reference page

    • docker build . -t <image_name>

  • Run the container

    • docker run -d -p 3389 <docker_image_name>

  • Run the container with AMD GPU hardware acceleration

    • docker run --rm -d -p 3389 --device=/dev/dri --device /dev/snd -v /opt:/opt -v /etc/amd:/etc/amd -v /etc/OpenCL:/etc/OpenCL -v /tmp/.X11-unix:/tmp/.X11-unix -e DISPLAY=unix$DISPLAY <docker_image_name>

  • Connect container with RDP session

    • run the following command to check the port number on the host
      
      docker ps

    • sample output:
      
      root@Docker:~# docker ps

CONTAINER ID MAGE COMMAND CREATED STATUS PORTS NAMES

8570dee06e52 xrdp_base:01 "/usr/bin/run.sh" 47 hours ago Up 47 hours 0.0.0.0:49184->3389/tcp, :::49184->3389/tcp relaxed_margulis

    • Launch RDP (Windows environment) or Remmina (Linux environment)

      • connect to the host IP address with the port number
      • Example: 192.168.1.63:49184
      • Use the credential: root/root

check the running containers

• list all the running containers
  • docker ps
• list all the containers include the stopped containers
  • docker ps -all
• list container ID
  • docker container ls -q | awk '{print $1}'
• list container process ID by given container ID
  • docker inspect --format '{{ .State.Pid }} <container_ID>

Common used Command for Docker container

• Stop container by the container ID
• docker stop <container_ID>
• Stop container by the docker image’s names
• docker ps -q --filter ancestor=<container_image_name> | xargs docker stop
• Stop all running containers
• docker stop $(docker ps -q)
• clean all the exited containers
  • docker system prune
• remove specific container
  • docker container rm <container_ID>
• process list in one container
• docker container top
• Details of one container config
• docker container inspect
• Performance stats for all containers
• docker container stats
• Start new container interactively
• docker container run -it
  To access a running container/ runn addition command in existing container
  • docker exec -it <docker_image> /bin/bash

Docker runtime options with Memory, CPUs

1. use “-m” or “–memory” option to limit the maximum amount memory the container can use
2. use “–cpuset-cpus” option to specify the logical CPU core allocate to the container
3. use “–cpus=“ option to specify how much of the available CPU resources a container can use

Docker Networks

• show docker networks
• docker network ls
• Inspect a network
• docker network inspect
• Create a network
• docker network create --driver
• Attach a network to container
• docker network connect
• Detach a network from container
  • docker network disconnect

Network bridge: Default Docker virtual network which is NAT network behind the host IP

Network host: It gains performance by skipping virtual networks but sacrifices security of containers model

Network none: Removes eth0 and only leaves with localhost interface in container
Network driver: Built-in or 3rd party extensions that gives you virtual network features

Docker network connect: Dynamically creates a NIC in a container on an existing virtual network

Docker Network Security:

• Create apps fo fronted/backend sit on same Docker network
• The inter-communication never leaves host
• All externally exposed ports closed by default
• You must manually expose port via ‘-p’ option

Docker Network: DNS

Docker with Vulkan API ( AMD GPU)

Running game with Vulkan API inside docker containers need to pass several environment variables

If the host graphic driver is AMD Proprietary driver make sure you passed the following environment variable when run/create the container

• -e VK_ICD_FILENAMES=/etc/vulkan/icd.d/amd_icd32.json:/etc/vulkan/icd.d/amd_icd64.json

If the above environment variables are not sufficient try add this

• -v /usr/lib:/usr/lib