|Dan Helfman f3222df767|
Remotely wake up your servers ... as-a-service!
The problem: Docker prevents bridge-networked containers from sending wake-on-LAN packets outside of the Docker network. That means standard Docker containers can't wake up remote machines. As a work-around, you can put them on the Docker host network, but that has security and interoperability implications—you may not want to expose your containers that way.
The solution: wake-on-lan-service runs on Docker's host network and sends wake-on-LAN packets on behalf of other containers running on a standard bridge network. This allows them to wake up remote machines—without themselves having to be on the host network.
You might find this service useful for use cases like running Home Assistant in a Docker container without putting it on the host network—while still allowing it to wake up remote machines.
How it works
This service listens on a port for TCP requests containing a MAC address to send a wake-on-LAN packet to. It expects plain TCP requests, not HTTP.
PORT: The TCP port to listen on for wake-on-LAN requests, defaults to 18888. Don't forget to open this port in your firewall.
Running the service
$ sudo docker run --detach --name wake-on-lan-service --host network \ --env PORT=18888 projects.torsion.org/witten/wake-on-lan-service
Or, with Docker Compose:
services: wake-on-lan-service: image: projects.torsion.org/witten/wake-on-lan-service restart: always network_mode: host environment: PORT: 18888
Using the service
From within another container running on a Docker bridge network (so, no need to run on the host network), execute:
echo 00:00:0a:bb:28:fc | nc -N host.docker.internal 18888
This example uses the OpenBSD netcat variant to send a TCP packet containing the requested MAC address to wake. The packet is sent to port 18888 on the host, where this container should be listening.
For this to work, you may need to configure your client container (the one
echo command) to support the special
docker run --add-host host.docker.internal:host-gateway .... Or,
with Docker Compose:
extra_hosts: - "host.docker.internal:host-gateway"
Alternatively, on Linux, you can try using the IP
If you happen to be using Home Assistant in Docker, here's how you might request wake-on-LAN of a remote server via wake-on-lan-service. This example is of an automation action in your Home Assistant configuration:
automation: - alias: my automation trigger: ... action: - service: shell_command.wake_my_server shell_command: wake_my_server: "echo 00:00:0a:bb:28:fc | nc host.docker.internal 18888"
(Home Assistant's Docker image includes netcat from busybox instead of OpenBSD
netcat, so omit the
Note that no authorization is performed on the service request, so be aware that anyone with network access to this service can wake arbitrary hosts by MAC address.