The Træfik Quickstart (Using Docker)

In this quickstart, we'll use Docker compose to create our demo infrastructure.

To save you some time, you can checkout the quickstart from the containous/traefik-quickstart repository and read along.

1 — Launch Træfik — Tell It to Listen to Docker

First, create the traefik-quickstart/traefik folder. In this folder, we will create a docker-compose.yml file where we will define a service reverse-proxy that uses the official Træfik image:

version: '3'

services:
  reverse-proxy:
    image: traefik #The official Traefik docker image
    command: --api --docker #Enables the web UI and tells Træfik to listen to docker
    ports:
      - "80:80"     #The HTTP port
      - "8080:8080" #The Web UI (enabled by --api)
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock #So that Traefik can listen to the Docker events

That's it. Now you can launch Træfik!

From the traefik-quickstart/traefik folder, run the following command (that will deploy the container defined in our docker-compose.yml file):

docker-compose up -d

If you'd like, you can open a browser and go to http://localhost:8080 to see Træfik's dashboard (we'll go back there once we have launched a service in step 2).

2 — Launch a Service — Træfik Detects It and Creates a Route for You

Now that we have a Træfik instance up and running, we will deploy new services.

Create the traefik-quickstart/services/docker-compose.yml file. There, we will define a new service (whoami) that is a simple webservice that outputs information about the machine it is deployed on (its IP address, host, and so on):

version: '3'

services:
  whoami:
    image: emilevauge/whoami #A container that exposes an API to show it's IP address
    labels:
      - "traefik.frontend.rule=Host:whoami.docker.localhost"

#We're deploying the services on the same network so that the containers can talk to each other
networks: 
   default: 
      external:
         name: traefik_default 

From the traefik-quickstart/services folder, run the following command to deploy your new container:

docker-compose up -d

Go back to your browser (http://localhost:8080) and see that Træfik has automatically detected the new container and updated its own configuration.

Now that Traefik has detected the service, a route is available and you can call your service! (Here, we're using curl)

curl -H Host:whoami.docker.localhost http://127.0.0.1

Shows the following output:

Hostname: 8656c8ddca6c
IP: 172.27.0.3
#...

3 — Launch More Instances — Traefik Load Balances Them

From the traefik-quickstart/services folder, run the following command to start more instances of your whoami services:

docker-compose up --scale whoami=2 -d

Go back to your browser (http://localhost:8080) and see that Træfik has automatically detected the new instance of the container.

Finally, see that Træfik load-balances between the two instances of your services by running the following command multiple times:

curl -H Host:whoami.docker.localhost http://127.0.0.1

The output will show alternatively one of the followings:

Hostname: 8656c8ddca6c
IP: 172.27.0.3
#...

Hostname: 8458f154e1f1
IP: 172.27.0.4
# ...

4 — Enjoy Træfik's Magic

Now that you have a basic understanding of how Træfik can automatically create the routes to your services and load balance them, it might be time to dive into the documentation and let Træfik work for you! Whatever your infrastructure is, there is probably an available Træfik backend that will do the job.

Our recommendation would be to see for yourself how simple it is to enable HTTPS with Træfik's let's encrypt integration using the dedicated user guide.