Ansible Role: Docker

An Ansible Role that installs Docker on Linux.

Requirements

None.

Role Variables

Available variables are listed below, along with default values (see defaults/main.yml):

# Edition can be one of: 'ce' (Community Edition) or 'ee' (Enterprise Edition).
docker_edition: 'ce'
docker_package: "docker-{{ docker_edition }}"
docker_package_state: present

The docker_edition should be either ce (Community Edition) or ee (Enterprise Edition). You can also specify a specific version of Docker to install using the distribution-specific format: Red Hat/CentOS: docker-{{ docker_edition }}-<VERSION>; Debian/Ubuntu: docker-{{ docker_edition }}=<VERSION>.

You can control whether the package is installed, uninstalled, or at the latest version by setting docker_package_state to present, absent, or latest, respectively. Note that the Docker daemon will be automatically restarted if the Docker package is updated. This is a side effect of flushing all handlers (running any of the handlers that have been notified by this and any other role up to this point in the play).

docker_service_manage: true
docker_service_state: started
docker_service_enabled: true
docker_restart_handler_state: restarted

Variables to control the state of the docker service, and whether it should start on boot. If you're installing Docker inside a Docker container without systemd or sysvinit, you should set docker_service_manage to false.

docker_install_compose_plugin: false
docker_compose_package: docker-compose-plugin
docker_compose_package_state: present

Docker Compose Plugin installation options. These differ from the below in that docker-compose is installed as a docker plugin (and used with docker compose) instead of a standalone binary.

docker_install_compose: true
docker_compose_version: "1.26.0"
docker_compose_arch: x86_64
docker_compose_path: /usr/local/bin/docker-compose

Docker Compose installation options.

docker_repo_url: https://download.docker.com/linux

The main Docker repo URL, common between Debian and RHEL systems.

docker_apt_release_channel: stable
docker_apt_arch: amd64
docker_apt_repository: "deb [arch={{ docker_apt_arch }}] {{ docker_repo_url }}/{{ ansible_distribution | lower }} {{ ansible_distribution_release }} {{ docker_apt_release_channel }}"
docker_apt_ignore_key_error: True
docker_apt_gpg_key: "{{ docker_repo_url }}/{{ ansible_distribution | lower }}/gpg"

(Used only for Debian/Ubuntu.) You can switch the channel to nightly if you want to use the Nightly release.

You can change docker_apt_gpg_key to a different url if you are behind a firewall or provide a trustworthy mirror. Usually in combination with changing docker_apt_repository as well.

docker_yum_repo_url: "{{ docker_repo_url }}/{{ (ansible_distribution == 'Fedora') | ternary('fedora','centos') }}/docker-{{ docker_edition }}.repo"docker_edition }}.repo
docker_yum_repo_enable_nightly: '0'
docker_yum_repo_enable_test: '0'
docker_yum_gpg_key: "{{ docker_repo_url }}/centos/gpg"

(Used only for RedHat/CentOS.) You can enable the Nightly or Test repo by setting the respective vars to 1.

You can change docker_yum_gpg_key to a different url if you are behind a firewall or provide a trustworthy mirror. Usually in combination with changing docker_yum_repository as well.

docker_users:
  - user1
  - user2

A list of system users to be added to the docker group (so they can use Docker on the server).

docker_daemon_options:
  storage-driver: "devicemapper"
  log-opts:
    max-size: "100m"

Custom dockerd options can be configured through this dictionary representing the json file /etc/docker/daemon.json.

Use with Ansible (and docker Python library)

Many users of this role wish to also use Ansible to then build Docker images and manage Docker containers on the server where Docker is installed. In this case, you can easily add in the docker Python library using the geerlingguy.pip role:

- hosts: all

  vars:
    pip_install_packages:
      - name: docker

  roles:
    - geerlingguy.pip
    - geerlingguy.docker

Dependencies

None.

Example Playbook

- hosts: all
  roles:
    - geerlingguy.docker

License

MIT / BSD

Sponsors

• We Manage: Helping start-ups and grown-ups scaling their infrastructure in a sustainable way.

The above sponsor(s) are supporting Jeff Geerling on GitHub Sponsors. You can sponsor Jeff's work too, to help him continue improving these Ansible open source projects!

Author Information

This role was created in 2017 by Jeff Geerling, author of Ansible for DevOps.