Many of the services installed by this playbook need to be exposed to the web (HTTP/HTTPS). This is handled by Traefik, which is installed by default if you have used the [example `vars.yml` file](../../examples/vars.yml).
Enabling the Traefik service, as shown above, automatically installs a [tecnativa/docker-socket-proxy](https://github.com/Tecnativa/docker-socket-proxy) service/container (powered by the [com.devture.ansible.role.container_socket_proxy](https://github.com/devture/com.devture.ansible.role.container_socket_proxy) Ansible role) to improve security by not mounting a Docker socket into the Traefik container.
This [Ansible role we use for Traefik](https://github.com/devture/com.devture.ansible.role.traefik) supports various configuration options. Feel free to consult [its `default/main.yml` variables file](https://github.com/devture/com.devture.ansible.role.traefik/blob/main/defaults/main.yml).
Below, you can find some guidance about common tweaks you may wish to do.
## Using another Traefik instance (not installing Traefik)
Sometimes you may already have a Traefik instance running on the server and you may wish to not have the playbook install Traefik.
To tell the playbook that you're running a Traefik instance and you'd still like all services installed by the playbook to be connected to that Traefik instance, you need the following configuration:
```yml
# Tell the playbook you're using Traefik installed in another way.
This will enable a Traefik [Dashboard](https://doc.traefik.io/traefik/operations/dashboard/) UI at `https://traefik.mash.example.com/dashboard/` (note the trailing `/`).
**WARNING**: enabling the dashboard on a hostname you use for something else (like `mash.example.com` in the configuration above) may cause conflicts. Enabling the Traefik Dashboard makes Traefik capture all `/dashboard` and `/api` requests and forward them to itself. If any of the services hosted on the same hostname requires any of these 2 URL prefixes, you will experience problems.
## Additional configuration
Use the `devture_traefik_configuration_extension_yaml` variable provided by the Traefik Ansible role to override or inject additional settings, even when no dedicated variable exists.
```yaml
# This is a contrived example.
# You can enable and secure the Dashboard using dedicated variables. See above.