kubespray/roles/docker/tasks/install.yml

---
- name: Install prerequisites for https transport
  apt: pkg={{ item }} state=present update_cache=yes
  with_items:
    - apt-transport-https
    - ca-certificates

- name: Configure docker apt repository
  template: src=docker.list.j2 dest=/etc/apt/sources.list.d/docker.list backup=yes

- name: Install docker-engine
  apt: pkg={{ item }} state=present force=yes update_cache=yes
  with_items:
    - aufs-tools
    - cgroupfs-mount
    - docker-engine=1.9.1-0~{{ ansible_distribution_release }}

- name: Copy default docker configuration
  template: src=default-docker.j2 dest=/etc/default/docker backup=yes
  notify: restart docker

- name: Copy Docker systemd unit file
  copy: src=systemd-docker.service dest=/lib/systemd/system/docker.service backup=yes
  notify: restart docker