---
# Reboot hosts with rolling strategy to avoid taking down redundant services
#
# Usage examples:
#   # Reboot a single host
#   ansible-playbook reboot.yml -l testvm01
#
#   # Reboot all test hosts (one at a time)
#   ansible-playbook reboot.yml -l tier_test
#
#   # Reboot all DNS servers safely (one at a time)
#   ansible-playbook reboot.yml -l role_dns
#
# Safety features:
#   - serial: 1 ensures only one host reboots at a time
#   - Waits for host to come back online before proceeding
#   - Groups hosts by role to avoid rebooting same-role hosts consecutively

- name: Reboot hosts (rolling)
  hosts: all
  serial: 1
  order: shuffle  # Randomize to spread out same-role hosts
  gather_facts: false

  vars:
    reboot_timeout: 300  # 5 minutes to wait for host to come back

  tasks:
    - name: Display reboot target
      ansible.builtin.debug:
        msg: "Rebooting {{ inventory_hostname }} (role: {{ role | default('none') }})"

    - name: Reboot the host
      ansible.builtin.systemd:
        name: reboot.target
        state: started
      async: 1
      poll: 0
      ignore_errors: true

    - name: Wait for host to come back online
      ansible.builtin.wait_for_connection:
        delay: 5
        timeout: "{{ reboot_timeout }}"

    - name: Display reboot result
      ansible.builtin.debug:
        msg: "{{ inventory_hostname }} rebooted successfully"