- name: Check if reboot is required
  hosts: all
  gather_facts: false
  become: true
  vars:
    reboot_machines: false  # default, override via --extra-vars

  tasks:
    - name: Check for /var/run/reboot-required
      stat:
        path: /var/run/reboot-required
      register: reboot_flag

    - name: Display reboot status
      debug:
        msg: "{{ inventory_hostname }} {{ 'REQUIRES' if reboot_flag.stat.exists else 'does NOT require' }} a reboot."

    - name: Reboot if required and reboot_machines flag is true
      reboot:
        msg: "Rebooting due to /var/run/reboot-required"
        pre_reboot_delay: 5
      when:
        - reboot_flag.stat.exists
        - reboot_machines | bool