UPDATE: This method is old and outdated. Most of the time this is probably what you actually want – https://docs.ansible.com/ansible/latest/modules/reboot_module.html.

Sometimes when using Ansible there is the need to reboot a server and wait for it to return. This simple recipe will allow you to achieve that while also getting some nice feedback so you know what is going on. You can place these tasks into a role or just in your playbook:

- name: Store target host and user
  set_fact:
  target_host: "{{ ansible_host }}"
  target_user: "{{ ansible_user }}"
 
- name: Reboot the server
  shell: sleep 2 && shutdown -r now "Ansible package updates triggered"
  async: 1
  poll: 0
  ignore_errors: true
 
- name: Wait for server to shutdown
  local_action: shell ssh -o BatchMode=yes -o ConnectTimeout=2 -o StrictHostKeyChecking=no "{{ target_user }}@{{ target_host }}" true
  register: result
  until: result.rc != 0
  failed_when: result.rc == -1
  retries: 200
  delay: 1
 
- name: Wait for server to be ready
  local_action: shell ssh -o BatchMode=yes -o ConnectTimeout=2 -o StrictHostKeyChecking=no "{{ target_user }}@{{ target_host }}" true
  register: result
  until: result.rc == 0
  retries: 200
  delay: 3