headscale/docs/ref/remote-cli.md
nblock 45104752f5 Refresh remote CLI documentation (#2216)
* Document to either use a minimal configuration file or environment
  variables to connect with a remote headscale instance.
* Document a workaround specific for headscale 0.23.0.
* Remove reference to ancient headscale version.
* Use `cli.insecure: true` or `HEADSCALE_CLI_INSECURE=1` to skip
  certificate verification.
* Style and typo fixes

Ref: #2193
2024-11-16 08:34:31 +03:00

3.7 KiB

Controlling headscale with remote CLI

This documentation has the goal of showing a user how-to control a headscale instance from a remote machine with the headscale command line binary.

Prerequisite

  • A workstation to run headscale (any supported platform, e.g. Linux).
  • A headscale server with gRPC enabled.
  • Connections to the gRPC port (default: 50443) are allowed.
  • Remote access requires an encrypted connection via TLS.
  • An API key to authenticate with the headscale server.

Create an API key

We need to create an API key to authenticate with the remote headscale server when using it from our workstation.

To create an API key, log into your headscale server and generate a key:

headscale apikeys create --expiration 90d

Copy the output of the command and save it for later. Please note that you can not retrieve a key again, if the key is lost, expire the old one, and create a new key.

To list the keys currently associated with the server:

headscale apikeys list

and to expire a key:

headscale apikeys expire --prefix "<PREFIX>"

Download and configure headscale

  1. Download the headscale binary from GitHub's release page. Make sure to use the same version as on the server.

  2. Put the binary somewhere in your PATH, e.g. /usr/local/bin/headscale

  3. Make headscale executable:

    chmod +x /usr/local/bin/headscale
    
  4. Provide the connection parameters for the remote headscale server either via a minimal YAML configuration file or via environment variables:

    === "Minimal YAML configuration file"

    ```yaml
    cli:
        address: <HEADSCALE_ADDRESS>:<PORT>
        api_key: <API_KEY_FROM_PREVIOUS_STEP>
    ```
    

    === "Environment variables"

    ```shell
    export HEADSCALE_CLI_ADDRESS="<HEADSCALE_ADDRESS>:<PORT>"
    export HEADSCALE_CLI_API_KEY="<API_KEY_FROM_PREVIOUS_STEP>"
    ```
    
    !!! bug
    
        Headscale 0.23.0 requires at least an empty configuration file when environment variables are used to
        specify connection details. See [issue 2193](https://github.com/juanfont/headscale/issues/2193) for more
        information.
    

    This instructs the headscale binary to connect to a remote instance at <HEADSCALE_ADDRESS>:<PORT>, instead of connecting to the local instance.

  5. Test the connection

    Let us run the headscale command to verify that we can connect by listing our nodes:

    headscale nodes list
    

    You should now be able to see a list of your nodes from your workstation, and you can now control the headscale server from your workstation.

Behind a proxy

It is possible to run the gRPC remote endpoint behind a reverse proxy, like Nginx, and have it run on the same port as headscale.

While this is not a supported feature, an example on how this can be set up on NixOS is shown here.

Troubleshooting

  • Make sure you have the same headscale version on your server and workstation.
  • Ensure that connections to the gRPC port are allowed.
  • Verify that your TLS certificate is valid and trusted.
  • If you don't have access to a trusted certificate (e.g. from Let's Encrypt), either:
    • Add your self-signed certificate to the trust store of your OS or
    • Disable certificate verification by either setting cli.insecure: true in the configuration file or by setting HEADSCALE_CLI_INSECURE=1 via an environment variable. We do not recommend to disable certificate validation.