# Running headscale in a container **Note:** the container documentation is maintained by the _community_ and there is no guarentee it is up to date, or working. ## Goal This documentation has the goal of showing a user how-to set up and run `headscale` in a container. [Docker](https://www.docker.com) is used as the reference container implementation, but there is no reason that it should not work with alternatives like [Podman](https://podman.io). The Docker image can be found on Docker Hub [here](https://hub.docker.com/r/headscale/headscale). ## Configure and run `headscale` 1. Prepare a directory on the host Docker node in your directory of choice, used to hold `headscale` configuration and the [SQLite](https://www.sqlite.org/) database: ```shell mkdir -p ./headscale/config cd ./headscale ``` 2. Create an empty SQlite datebase in the headscale directory: ```shell touch ./config/db.sqlite ``` 3. **(Strongly Recommended)** Download a copy of the [example configuration](../config-example.yaml) from the [headscale repository](https://github.com/juanfont/headscale/). Using wget: ```shell wget -O ./config/config.yaml https://raw.githubusercontent.com/juanfont/headscale/main/config-example.yaml ``` Using curl: ```shell curl https://raw.githubusercontent.com/juanfont/headscale/main/config-example.yaml -o ./config/config.yaml ``` **(Advanced)** If you would like to hand craft a config file **instead** of downloading the example config file, create a blank `headscale` configuration in the headscale directory to edit: ```shell touch ./config/config.yaml ``` Modify the config file to your preferences before launching Docker container. Here are some settings that you likely want: ```yaml # Change to your hostname or host IP server_url: http://your-host-name:8080 # Listen to 0.0.0.0 so it's accessible outside the container metrics_listen_addr: 0.0.0.0:9090 # The default /var/lib/headscale path is not writable in the container private_key_path: /etc/headscale/private.key # The default /var/lib/headscale path is not writable in the container noise: private_key_path: /etc/headscale/noise_private.key # The default /var/lib/headscale path is not writable in the container db_path: /etc/headscale/db.sqlite ``` 4. Start the headscale server while working in the host headscale directory: ```shell docker run \ --name headscale \ --detach \ --volume $(pwd)/config:/etc/headscale/ \ --publish 127.0.0.1:8080:8080 \ --publish 127.0.0.1:9090:9090 \ headscale/headscale: \ headscale serve ``` Note: use `0.0.0.0:8080:8080` instead of `127.0.0.1:8080:8080` if you want to expose the container externally. This command will mount `config/` under `/etc/headscale`, forward port 8080 out of the container so the `headscale` instance becomes available and then detach so headscale runs in the background. 5. Verify `headscale` is running: Follow the container logs: ```shell docker logs --follow headscale ``` Verify running containers: ```shell docker ps ``` Verify `headscale` is available: ```shell curl http://127.0.0.1:9090/metrics ``` 6. Create a namespace ([tailnet](https://tailscale.com/kb/1136/tailnet/)): ```shell docker exec headscale \ headscale namespaces create myfirstnamespace ``` ### Register a machine (normal login) On a client machine, execute the `tailscale` login command: ```shell tailscale up --login-server YOUR_HEADSCALE_URL ``` To register a machine when running `headscale` in a container, take the headscale command and pass it to the container: ```shell docker exec headscale \ headscale --namespace myfirstnamespace nodes register --key ``` ### Register machine using a pre authenticated key Generate a key using the command line: ```shell docker exec headscale \ headscale --namespace myfirstnamespace preauthkeys create --reusable --expiration 24h ``` This will return a pre-authenticated key that can be used to connect a node to `headscale` during the `tailscale` command: ```shell tailscale up --login-server --authkey ``` ## Debugging headscale running in Docker The `headscale/headscale` Docker container is based on a "distroless" image that does not contain a shell or any other debug tools. If you need to debug your application running in the Docker container, you can use the `-debug` variant, for example `headscale/headscale:x.x.x-debug`. ### Running the debug Docker container To run the debug Docker container, use the exact same commands as above, but replace `headscale/headscale:x.x.x` with `headscale/headscale:x.x.x-debug` (`x.x.x` is the version of headscale). The two containers are compatible with each other, so you can alternate between them. ### Executing commands in the debug container The default command in the debug container is to run `headscale`, which is located at `/bin/headscale` inside the container. Additionally, the debug container includes a minimalist Busybox shell. To launch a shell in the container, use: ``` docker run -it headscale/headscale:x.x.x-debug sh ``` You can also execute commands directly, such as `ls /bin` in this example: ``` docker run headscale/headscale:x.x.x-debug ls /bin ``` Using `docker exec` allows you to run commands in an existing container.