kata-containers/install/docker/ubuntu-docker-install.md

Install Docker for Kata Containers on Ubuntu

Note:

• This guide assumes you have already installed the Kata Containers packages.

1. Install the latest version of Docker with the following commands:

   Note: This step is only required if Docker is not installed on the system.

   $ sudo -E apt-get -y install apt-transport-https ca-certificates software-properties-common
   $ curl -sL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
   $ arch=$(dpkg --print-architecture)
   $ sudo -E add-apt-repository "deb [arch=${arch}] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
   $ sudo -E apt-get update
   $ sudo -E apt-get -y install docker-ce
   

   For more information on installing Docker please refer to the Docker Guide.

2. Configure Docker to use Kata Containers by default with one of the following methods:

   1. systemd

      $ sudo mkdir -p /etc/systemd/system/docker.service.d/
      $ cat <<EOF | sudo tee /etc/systemd/system/docker.service.d/kata-containers.conf
      [Service]
      ExecStart=
      ExecStart=/usr/bin/dockerd -D --add-runtime kata-runtime=/usr/bin/kata-runtime --default-runtime=kata-runtime
      EOF
      

   2. Docker daemon.json

      Add the following definitions to /etc/docker/daemon.json:

      {
        "default-runtime": "kata-runtime",
        "runtimes": {
          "kata-runtime": {
            "path": "/usr/bin/kata-runtime"
          }
        }
      }
      

3. Restart the Docker systemd service with the following commands:

   $ sudo systemctl daemon-reload
   $ sudo systemctl restart docker
   

4. Run Kata Containers

   You are now ready to run Kata Containers:

   $ sudo docker run busybox uname -a
   

   The previous command shows details of the kernel version running inside the container, which is different to the host kernel version.