Traefik with Docker Networks - docker

Question

I really don't get how to use traefik with docker networks.
I try to run "wekan" kanban. If I bind ports to host, it works perfectly, so it really is about adressing it through traefik. Here is my docker-config:
version: '2'
services:
wekandb:
image: mongo:3.2.14
container_name: wekan-db
command: mongod --smallfiles --oplogSize 128
networks:
- wekan-tier
expose:
- 27017
volumes:
- wekan-db:/data/db
- wekan-db-dump:/dump
wekan:
image: wekanteam/wekan:latest
container_name: wekan-app
networks:
- wekan-tier
# ports:
# - 8081:80
environment:
- MONGO_URL=mongodb://wekandb:27017/wekan
- ROOT_URL=https://wekan.domain.com
depends_on:
- wekandb
labels:
- "traefik.port=80"
- "traefik.backend=wekan"
- "traefik.frontend.rule=Host:wekan.domain.com"
- "traefik.docker.network=wekan_wekan-tier"
volumes:
wekan-db:
driver: local
wekan-db-dump:
driver: local
networks:
wekan-tier:
driver: bridge
I can't seem to find a way to access the damn thing... Your answer will be greatly appreciated, not only will it allow me to run Wekan, but also to update my older services where I used linking:linking instead of Docker Networks - Linking being now deprecated.

Answer 1

I believe you have more than one issue here.
First, in your compose you don't have Traefik service, it is OK, Traefik will be able to see containers from the services here, but Traefik will not be able to send the request to it, because Traefik service and wekan service does not share the same network.
So to fix that you need to create an specific network to Traefik and set it in your compose file also.
Example:
$ docker network create traefik-net
$ docker service --name traefik --network traefik-net .... traefik ....
Second, you need to define the network Traefik will use to connect with your service, this network must be one shared with Traefik service.
So your wekan service needs to be like this:
wekan:
image: wekanteam/wekan:latest
container_name: wekan-app
networks:
- wekan-tier
- traefik-net
environment:
- MONGO_URL=mongodb://wekandb:27017/wekan
- ROOT_URL=https://wekan.domain.com
depends_on:
- wekandb
labels:
- "traefik.port=80"
- "traefik.backend=wekan"
- "traefik.frontend.rule=Host:wekan.domain.com"
- "traefik.docker.network=traefik-net"

Answer 2

I have modified your docker-compose file to make it work:
version: '3'
services:
web:
image: wekanteam/wekan:latest
networks:
- wekan-tier
environment:
- MONGO_URL=mongodb://wekandb:27017/wekan
- ROOT_URL=https://wekan.domain.com
labels:
- "traefik.port=80"
- "traefik.docker.network=wekan_wekan-tier"
wekandb:
image: mongo:3.2
command: mongod --smallfiles --oplogSize 128
networks:
- wekan-tier
expose:
- 27017
volumes:
- wekan-db:/data/db
- wekan-db-dump:/dump
traefik:
image: 'traefik:1.6'
command: --web --docker --docker.watch --docker.domain=local --logLevel=DEBUG
labels:
- traefik.docker.network=wekan-tier
- traefik.port=8080
ports:
- '80:80'
- '8080:8080'
volumes:
- '/var/run/docker.sock:/var/run/docker.sock'
networks:
- wekan-tier
volumes:
wekan-db:
driver: local
wekan-db-dump:
driver: local
networks:
wekan-tier:
driver: bridge
Now start containers with the following command:
$ docker-compose -p wekan up -d
To check that traefik is working go to http://localhost:8080/, if you have problems stop your apache server using $ service apache2 stop. On the other hand, if you can see the traefik interface then add the following line to your /etc/hosts file:
127.0.0.1 web.wekan.local
Now go to http://web.wekan.local and you should see Wekan login page :)