Reboot server if required and wait for it to come back.

reboot.yml

- name: Reboot system if required
  command: shutdown -r now 'Rebooting to complete system upgrade' removes=/var/run/reboot-required
  register: reboot_required
  tags:
    - apt
    - updates

- name: Wait for server to come back.
  local_action: wait_for port={{ ansible_ssh_port }} host="{{ ansible_ssh_host | default(inventory_hostname) }}" search_regex=OpenSSH delay=10
  when: reboot_required.changed
  sudo: false
  tags:
    - apt
    - updates