How to specify server port in dynamic configuration?

Traefik Traefik v2
#1

We are able to define the following label for the service:

traefik.http.services.myservice.loadbalancer.server.port=9000

What is the equivalent of the above line in file provider? I suppose it should be something like this, but I didn't find any documentation.

http:
  services:
    myservice:
      loadbalancer:
        server:
          port: 9000
#2

Hello,

In the file provider, a server must be describe by an URL:

http:
  services:
    my-service:
      loadBalancer:
        servers:
          - url: "http://foobar.com:9080"

https://docs.traefik.io/v2.0/routing/services/#servers

The label traefik.http.services.myservice.loadbalancer.server.port exists because for a Docker container a user cannot known the IP.

#3

Let's say I have the following dynamic configuration saved in file in config folder:

http:
  services:
    traefik:
      loadBalancer:
        passHostHeader: true
    whoami:
      loadBalancer:
        passHostHeader: true
        sticky:
          cookie:
            name: StickyCookie
  routers:
    traefik:
      rule: "Host(`example.com`)"
      entryPoints:
        - "traefik"
      service: traefik
    whoami:
      rule: "Host(`example.me`)"
      entryPoints:
        - "web"
      service: whoami

And the following docker-compose file:

version: "3.7"

services:
  traefik:
    image: "traefik:v2.0"
    networks:
      - traefik-net
    ports:
      - "9000:9000"
      - "5000:5000"
    volumes:
      - "/var/run/docker.sock:/var/run/docker.sock:ro"
      - "./config/:/etc/traefik"
    deploy:
      replicas: 1
      labels:
        - "traefik.http.services.traefik.loadbalancer.server.port=8080"

networks:
  traefik-net:
    external:
      name: traefik-net

When I execute docker stack deploy, it creates 3 services:

  1. traefik (provider file)
  2. traefik (provider Docker)
  3. whoami (provider file)

This is not what I want. I just want to specify port for traefik service which is defined in file, I don't want to create another service. How can I reference existing traefik service from labels section so that it wouldn't create new one?

#4

Why are you using file you define routers on containers?
why not just use labels?

Only labels (I recommend):

version: "3.7"

services:
  traefik:
    image: "traefik:v2.0"
    networks:
      - traefik-net
    ports:
      - "9000:9000"
      - "5000:5000"
    volumes:
      - "/var/run/docker.sock:/var/run/docker.sock:ro"
      - "./config/:/etc/traefik"
    deploy:
      replicas: 1
      labels:
        - "traefik.http.routers.traefik.rule=Host(`example.com`)"
        - "traefik.http.routers.traefik.entrypoints=traefik"
        - "traefik.http.routers.traefik.service=api@internal"
        - "traefik.http.services.traefik.loadbalancer.server.port=8080" # noop

  whoami:
    image: containous/whoami:v1.3.0
    networks:
      - traefik-net
    deploy:
      labels:
        - "traefik.http.routers.whoami.rule: Host(`example.me`)"
        - "traefik.http.routers.myrouter.entrypoints=web"
        - "traefik.http.services.whoami.loadbalancer.sticky.cookie.name=StickyCookie"

networks:
  traefik-net:
    external:
      name: traefik-net

Mixed labels and file (I don't recommend in your case):

version: "3.7"

services:
  traefik:
    image: "traefik:v2.0"
    networks:
      - traefik-net
    ports:
      - "9000:9000"
      - "5000:5000"
    volumes:
      - "/var/run/docker.sock:/var/run/docker.sock:ro"
      - "./config/:/etc/traefik"
    deploy:
      replicas: 1
      labels:
        - "traefik.enable=false"

  whoami:
    image: containous/whoami:v1.3.0
    networks:
      - traefik-net
    deploy:
      labels:
        - "traefik.http.services.whoami.loadbalancer.sticky.cookie.name=StickyCookie"

networks:
  traefik-net:
    external:
      name: traefik-net

http:
  routers:
    traefik:
      rule: "Host(`example.com`)"
      entryPoints:
        - "traefik"
      service: api@internal
    whoami:
      rule: "Host(`example.me`)"
      entryPoints:
        - "web"
      service: whoami@docker

It cannot be done by using only file.