Traefik and external services

No worries for the question. It's not terribly intuitive.

The configs live on the Traefik server. In my static traefik.yml config I have the following providers section, which adds the file provider in addition to the docker provider which you likely already have:

providers:
  docker:
    endpoint: "unix:///var/run/docker.sock"
    exposedByDefault: false
  file:
    directory: /config
    watch: true

And in the /config folder mapped into the Traefik container I have several files for services external to docker. You can combine them or keep them separate since the watch: true setting tells it to read in all files (and it's near instant when you create them, no need to restart Traefik).

Here is my homeassistant.yml in that folder (I have a separate VM running HASS outside of Docker/Traefik):

http:
  routers:
    homeassistant-rtr:
      entryPoints:
      - https
      service: homeassistant-svc
      rule: "Host(`home.example.com`)"
      tls:
        certResolver: examplecom-dns

  services:
    homeassistant-svc:
      loadBalancer:
        servers:
          - url: "http://hass1.internal.local:8123"

Hope this helps!