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 a format like docker-{{ docker_edition }}-<VERSION>. And 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.

docker_restart_on_package_change: True

Whether to restart the Docker daemon after the Docker package is installed or updated. If this is set to True, this role will flush all handlers (run any of the handlers that have been notified by this and any other role up to this point in the play). The default setting helps avoid firewall clashes with Docker rules (e.g. when using custom iptables rules or the geerlingguy.firewall Ansible role).

docker_service_state: started
docker_service_enabled: yes
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 these to stopped and set the enabled variable to no.

docker_install_compose: True
docker_compose_version: "1.21.2"
docker_compose_path: /usr/local/bin/docker-compose

Docker Compose installation options.

docker_apt_release_channel: stable
docker_apt_arch: amd64
docker_apt_repository: "deb [arch={{ docker_apt_arch }}] https://download.docker.com/linux/{{ ansible_distribution|lower }} {{ ansible_distribution_release }} {{ docker_apt_release_channel }}"
docker_apt_ignore_key_error: True

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

docker_yum_repo_url: https://download.docker.com/linux/centos/docker-{{ docker_edition }}.repo
docker_yum_repo_enable_edge: 0
docker_yum_repo_enable_test: 0

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

docker_users:
  - user1
  - user2

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

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

Author Information

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