---
- name: Ensure hostname set
  hostname:
    name: "{{ inventory_hostname }}"
  when: not inventory_hostname|trim is match('(\d{1,3}\.){3}\d{1,3}')
  become: yes
  register: hostname_set

- name: Reboot host and wait for it to restart
  reboot:
    msg: "Reboot initiated by Ansible"
    connect_timeout: 5
    reboot_timeout: 600
    pre_reboot_delay: 0
    post_reboot_delay: 30
    test_command: whoami
  when: hostname_set.changed