Traefik 2.0: Paranoid about mounting /var/run/docker.sock?
If you have followed our previous guides, you mount the Docker Socket (
/var/run/docker.sock) into the Traefik container. If someone gets access into the Traefik container, they can gain full access to your host machine. This makes our paranoia level increase slightly…
We found a nice little container (Socket-Proxy) which “filters” all requests to the Docker API. We can allow only
get requests to the Docker API and restrict it to
The Socket Proxy uses the official Alpine-based HAProxy image. It blocks access to the Docker socket API according to the environment variables you set. It returns a
HTTP 403 Forbidden status for those dangerous requests that should never happen.
Let’s create the socket-proxy container (
version: "3.6" services: socket-proxy: image: tecnativa/docker-socket-proxy container_name: socket-proxy restart: unless-stopped volumes: - /var/run/docker.sock:/var/run/docker.sock:ro environment: CONTAINERS: 1 networks: - proxy networks: proxy: external: true
The environment variable
CONTAINERS: 1 tells the proxy to grant
get requests to
/containers/* from the Docker API.
Post requests are disabled by default.
All possible settings are described here.
Now we have to change the endpoint in the providers section of the traefik.yml file (
api: dashboard: true debug: false entryPoints: http: address: ":80" https: address: ":443" providers: docker: endpoint: "tcp://socket-proxy:2375" watch: true exposedbydefault: false
Restart the Traefik container and feel a little bit more safe!