The playbook installs a [Coturn](https://github.com/coturn/coturn) TURN server by default, so that clients can make audio/video calls even from [NAT](https://en.wikipedia.org/wiki/Network_address_translation)-ed networks.
By default, the Synapse chat server is configured, so that it points to the Coturn TURN server installed by the playbook.
## Disabling Coturn
If, for some reason, you'd like to prevent the playbook from installing Coturn, you can use the following configuration:
```yaml
matrix_coturn_enabled: false
```
In that case, Synapse would not point to any Coturn servers and audio/video call functionality may fail.
In the `hosts` file we explicitly ask for your server's external IP address when defining `ansible_host`, because the same value is used for configuring Coturn.
If you'd rather use a local IP for `ansible_host`, make sure to set up `matrix_coturn_turn_external_ip_address` replacing `YOUR_PUBLIC_IP` with the pubic IP used by the server.
If you'd like to rely on external IP address auto-detection (not recommended unless you need it), set `matrix_coturn_turn_external_ip_address` to an empty value. The playbook will automatically contact an [EchoIP](https://github.com/mpolden/echoip)-compatible service (`https://ifconfig.co/json` by default) to determine your server's IP address. This API endpoint is configurable via the `matrix_coturn_turn_external_ip_address_auto_detection_echoip_service_url` variable.
If your server has multiple external IP addresses, the Coturn role offers a different variable for specifying them:
```yaml
# Note: matrix_coturn_turn_external_ip_addresses is different than matrix_coturn_turn_external_ip_address