Running headscale behind a reverse proxy is useful when running multiple applications on the same server, and you want to reuse the same external IP and port - usually tcp/443 for HTTPS.
WebSockets support is required when using the headscale embedded DERP server. In this case, you will also need to expose the UDP port used for STUN (by default, udp/3478). Please check our [config-example.yaml](https://github.com/juanfont/headscale/blob/main/config-example.yaml).
Headscale can be configured not to use TLS, leaving it to the reverse proxy to handle. Add the following configuration values to your headscale config file.
```yaml
server_url: https://<YOUR_SERVER_NAME> # This should be the FQDN at which headscale will be served
The following example configuration can be used in your nginx setup, substituting values as necessary. `<IP:PORT>` should be the IP address and port where headscale is running. In most cases, this will be `http://localhost:8080`.
If you using [Istio](https://istio.io/) ingressgateway or [Envoy](https://www.envoyproxy.io/) as reverse proxy, there are some tips for you. If not set, you may see some debug log in proxy as below:
You need add a new upgrade_type named `tailscale-control-protocol`. [see detail](https://www.envoyproxy.io/docs/envoy/latest/api-v3/extensions/filters/network/http_connection_manager/v3/http_connection_manager.proto#extensions-filters-network-http-connection-manager-v3-httpconnectionmanager-upgradeconfig)
The following Caddyfile is all that is necessary to use Caddy as a reverse proxy for headscale, in combination with the `config.yaml` specifications above to disable headscale's built in TLS. Replace values as necessary - `<YOUR_SERVER_NAME>` should be the FQDN at which headscale will be served, and `<IP:PORT>` should be the IP address and port where headscale is running. In most cases, this will be `localhost:8080`.
```
<YOUR_SERVER_NAME> {
reverse_proxy <IP:PORT>
}
```
Caddy v2 will [automatically](https://caddyserver.com/docs/automatic-https) provision a certficate for your domain/subdomain, force HTTPS, and proxy websockets - no further configuration is necessary.
For a slightly more complex configuration which utilizes Docker containers to manage Caddy, Headscale, and Headscale-UI, [Guru Computing's guide](https://blog.gurucomputing.com.au/smart-vpns-with-headscale/) is an excellent reference.
The following minimal Apache config will proxy traffic to the Headscale instance on `<IP:PORT>`. Note that `upgrade=any` is required as a parameter for `ProxyPass` so that WebSockets traffic whose `Upgrade` header value is not equal to `WebSocket` (i. e. Tailscale Control Protocol) is forwarded correctly. See the [Apache docs](https://httpd.apache.org/docs/2.4/mod/mod_proxy_wstunnel.html) for more information on this.