Wake on LAN & Shutdown

Wake on LAN can be performed with the following Ansible playbook:

- name: Wake on LAN
  hosts: computers
  gather_facts: no
  
  roles:
  - role: ufrmath.computer_labs.wol
    broadcast: 10.0.2.255

which uses the role ufrmath.computer_labs.wol

Note that a non-expiring Ansible cache is needed (consider adding fact_caching with fact_caching_timeout=0 to Ansible configuration), as the MAC addresses need to be known while the computers are off.

down the computers, it suffices to run the following playbook:

- name: Shutdown computers
  hosts: computers
  gather_facts: no
  
  tasks:

  - name: Shutdown
    command: shutdown +1
    become: true