trfore/docker-ubuntu2204-systemd repository overview

⁠docker-ubuntu2204-systemd

A minimal systemd enabled Ubuntu 22.04 Docker image for testing Ansible roles with Molecule.

NOTE: This image does NOT contain Ansible tooling, e.g. ansible-core or yamllint. Thus, the use case is as target host for Ansible controllers or within the Molecule create/converge/test cycle.

⁠Docker Pull Command

docker pull trfore/docker-ubuntu2204-systemd

⁠How to Build

This image is built on Docker Hub automatically any time the upstream OS image is rebuilt, and any time a commit is made or merged to the main branch. But if you need to build the image on your own locally, do the following:

1. Install docker⁠
2. Clone the repo, git clone https://github.com/trfore/docker-ubuntu2204-systemd.git
3. cd into the directory
4. Run docker build --tag trfore/docker-ubuntu2204-systemd .

⁠How to Use

⁠Within Molecule Scenario

• Add the following code to your molecule scenario file, e.g. molecule/default/molecule.yml.

  platforms:
    - name: ${MOLECULE_NAME:-instance}
      image: ${MOLECULE_IMAGE:-trfore/docker-ubuntu2204-systemd}
      command: ${MOLECULE_COMMAND:-""}
      tmpfs:
        - /run
        - /tmp
      volumes:
        - /sys/fs/cgroup:/sys/fs/cgroup:rw
      cgroupns_mode: host
      privileged: true
      pre_build_image: true
  

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⁠Interactively Using Docker

• Install docker⁠

• Build an image locally (see above) or pull from Docker Hub: docker pull trfore/docker-ubuntu2204-systemd:latest

• On Docker with Cgroup V1 (e.g. Ubuntu 20.04), run a container from the image:

  docker run -d -it --name ubuntu2204-systemd --privileged --cgroupns=host --tmpfs=/run --tmpfs=/tmp --volume=/sys/fs/cgroup:/sys/fs/cgroup:ro trfore/docker-ubuntu2204-systemd:latest
  

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• On Docker with Cgroup V2 (e.g. Ubuntu 22.04), run a container from the image:

  docker run -d -it --name ubuntu2204-systemd --privileged --cgroupns=host --tmpfs=/run --tmpfs=/tmp --volume=/sys/fs/cgroup:/sys/fs/cgroup:rw trfore/docker-ubuntu2204-systemd:latest
  

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• Use it, ex:

  docker exec -it ubuntu2204-systemd /bin/bash
  

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⁠Using Podman

• Podman defaults to running containers in systemd mode, --systemd=true, and will mount the required tmpfs and cgroup filesystem. See Podman Docs: Commands run --systemd⁠ for details.

  podman run -d -it --name ubuntu2204-systemd docker.io/trfore/docker-ubuntu2204-systemd:latest
  

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⁠Additional Images

⁠Maintainers

Taylor Fore (https://github.com/trfore⁠)

⁠Acknowledgements

Inspired by Jeff Geerling's (@geerlingguy⁠), CentOS 8, Debian 10/11, and Ubuntu 20/22 docker images for ansible, geerlingguy/docker-*-ansible⁠.

⁠References

• https://molecule.readthedocs.io/en/stable/index.html⁠
• https://molecule.readthedocs.io/en/stable/examples.html#systemd-container⁠
• https://developers.redhat.com/blog/2016/09/13/running-systemd-in-a-non-privileged-container⁠
• github runner - ubuntu 20.04⁠ preinstalled software
• github runner - ubuntu 22.04⁠ preinstalled software