Home Assistant

Wake on LAN Switch

The wake_on_lan (WOL) switch platform allows you to turn on a WOL enabled computer.

The WOL switch can only turn on your computer and monitor the state. There is no universal way to turn off a computer remotely. The turn_off variable is there to help you call a script when you have figured out how to remotely turn off your computer. See below for suggestions on how to do this.

To enable this switch in your installation, add the following to your configuration.yaml file:

# Example configuration.yml entry
switch:
  - platform: wake_on_lan
    mac_address: "00-01-02-03-04-05"

Configuration variables:

  • mac_address (Required): MAC address to send the wake up command to.
  • name (Optional): The name of the switch. Default is ‘Wake on LAN’.
  • host (Optional): The IP address or hostname to check the state of the device (on/off).
  • turn_off (Optional): Defines an action to run when the switch is turned off.
  • broadcast_address (Optional): The IP address of the host to send the magic packet to (default 255.255.255.255).

Examples

Here are some real life examples of how to use the turn_off variable.

Suspending Linux

Suggested recipe for letting the turn_off script suspend a Linux computer (the target) from Home Assistant running on another Linux computer (the server).

  1. On the server, log in as the user account Home Assistant is running under. (I’m using hass in this example)
  2. On the server, create ssh keys by running ssh-keygen. Just press enter on all questions.
  3. On the target, create a new account that Home Assistant can ssh into: sudo adduser hass. Just press enter on all questions except password. I recommend using the same user name as on the server. If you do, you can leave out hass@ in the ssh commands below.
  4. On the server, transfer your public ssh key by ssh-copy-id hass@TARGET where TARGET is your target machine’s name or IP address. Enter the password you created in step 3.
  5. On the server, verify that you can reach your target machine without password by ssh TARGET.
  6. On the target, we need to let the hass user execute the program needed to suspend/shut down the target computer. I’m using pm-suspend, use poweroff to turn off the computer. First, get the full path: which pm-suspend. On my system, this is /usr/sbin/pm-suspend.
  7. On the target, using an account with sudo access (typically your main account), sudo visudo. Add this line last in the file: hass ALL=NOPASSWD:/usr/sbin/pm-suspend, where you replace hass with the name of your user on the target, if different, and /usr/sbin/pm-suspend with the command of your choice, if different.
  8. On the server, add the following to your configuration, replacing TARGET with the target’s name:
switch:
  - platform: wake_on_lan
    name: "TARGET"
    ...
    turn_off:
      service: shell_command.turn_off_TARGET

shell_command:
  turn_off_TARGET: 'ssh hass@TARGET sudo pm-suspend'