headscale/docs/reverse-proxy.md

# Running headscale behind a reverse proxy

!!! warning "Community documentation"

    This page is not actively maintained by the headscale authors and is
    written by community members. It is _not_ verified by `headscale` developers.

    **It might be outdated and it might miss necessary steps**.

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

The reverse proxy MUST be configured to support WebSockets to communicate with Tailscale clients.

WebSockets support is also 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).

### Cloudflare

Running headscale behind a cloudflare proxy or cloudflare tunnel is not supported and will not work as Cloudflare does not support WebSocket POSTs as required by the Tailscale protocol. See [this issue](https://github.com/juanfont/headscale/issues/1468)

### TLS

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
listen_addr: 0.0.0.0:8080
metrics_listen_addr: 0.0.0.0:9090
tls_cert_path: ""
tls_key_path: ""
```

## nginx

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`.

```Nginx
map $http_upgrade $connection_upgrade {
    default      upgrade;
    ''           close;
}

server {
    listen 80;
	listen [::]:80;

	listen 443      ssl http2;
	listen [::]:443 ssl http2;

    server_name <YOUR_SERVER_NAME>;

    ssl_certificate <PATH_TO_CERT>;
    ssl_certificate_key <PATH_CERT_KEY>;
    ssl_protocols TLSv1.2 TLSv1.3;

    location / {
        proxy_pass http://<IP:PORT>;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection $connection_upgrade;
        proxy_set_header Host $server_name;
        proxy_redirect http:// https://;
        proxy_buffering off;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        add_header Strict-Transport-Security "max-age=15552000; includeSubDomains" always;
    }
}
```

## istio/envoy

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:

```log
Sending local reply with details upgrade_failed
```

### Envoy

You need to add a new upgrade_type named `tailscale-control-protocol`. [see details](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)

### Istio

Same as envoy, we can use `EnvoyFilter` to add upgrade_type.

```yaml
apiVersion: networking.istio.io/v1alpha3
kind: EnvoyFilter
metadata:
  name: headscale-behind-istio-ingress
  namespace: istio-system
spec:
  configPatches:
    - applyTo: NETWORK_FILTER
      match:
        listener:
          filterChain:
            filter:
              name: envoy.filters.network.http_connection_manager
      patch:
        operation: MERGE
        value:
          typed_config:
            "@type": type.googleapis.com/envoy.extensions.filters.network.http_connection_manager.v3.HttpConnectionManager
            upgrade_configs:
              - upgrade_type: tailscale-control-protocol
```

## Caddy

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 certificate 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.

## Apache

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.

```
<VirtualHost *:443>
	ServerName <YOUR_SERVER_NAME>

	ProxyPreserveHost On
	ProxyPass / http://<IP:PORT>/ upgrade=any

	SSLEngine On
	SSLCertificateFile <PATH_TO_CERT>
	SSLCertificateKeyFile <PATH_CERT_KEY>
</VirtualHost>
```