Docker Installation

Docker is the foundation of the Docker-only track and is also used on K3s nodes for local image builds and cross-platform compilation.

What this page covers

Installing Docker Engine on Ubuntu Server
Post-install steps: adding your user to the docker group
Cross-platform build support with QEMU and docker buildx
Docker Compose v2 installation

Installing Docker Engine

The recommended method uses Docker's official apt repository:

curl -fsSL https://get.docker.com | sh
sudo usermod -aG docker $USER

Log out and back in after adding yourself to the docker group.

Cross-build configuration

If you need to build images for different architectures (e.g., linux/arm64 on an amd64 host), install QEMU emulation support:

docker run --privileged --rm tonistiigi/binfmt --install all
docker buildx create --use --name multiarch

Docker Notes