Quick Start

A Simple Use Case Using Docker

quickstart-diagram

Launch Traefik With the Docker Provider

Create a docker-compose.yml file where you will define a reverse-proxy service that uses the official Traefik image:

  1. version: '3'
  3. services:
  4.   reverse-proxy:
  5.     # The official v2 Traefik docker image
  6.     image: traefik:v2.5
  7.     # Enables the web UI and tells Traefik to listen to docker
  8.     command: --api.insecure=true --providers.docker
  9.     ports:
  10.       # The HTTP port
  11.       - "80:80"
  12.       # The Web UI (enabled by --api.insecure=true)
  13.       - "8080:8080"
  14.     volumes:
  15.       # So that Traefik can listen to the Docker events
  16.       - /var/run/docker.sock:/var/run/docker.sock

That’s it. Now you can launch Traefik!

Start your reverse-proxy with the following command:

  1. docker-compose up -d reverse-proxy

You can open a browser and go to http://localhost:8080/api/rawdata to see Traefik’s API rawdata (we’ll go back there once we have launched a service in step 2).

Traefik Detects New Services and Creates the Route for You

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

Edit your docker-compose.yml file and add the following at the end of your file.

  1. # ...
  2.   whoami:
  3.     # A container that exposes an API to show its IP address
  4.     image: traefik/whoami
  5.     labels:
  6.       - "traefik.http.routers.whoami.rule=Host(`whoami.docker.localhost`)"

The above defines whoami: a simple web service that outputs information about the machine it is deployed on (its IP address, host, and so on).

Start the whoami service with the following command:

  1. docker-compose up -d whoami

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

When Traefik detects new services, it creates the corresponding routes so you can call them … let’s see! (Here, we’re using curl)

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

Shows the following output:

  1. Hostname: a656c8ddca6c
  2. IP: 172.27.0.3
  3. #...

More Instances? Traefik Load Balances Them

Run more instances of your whoami service with the following command:

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

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

Finally, see that Traefik load-balances between the two instances of your service by running the following command twice:

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

The output will show alternatively one of the followings:

  1. Hostname: a656c8ddca6c
  2. IP: 172.27.0.3
  3. #...
  1. Hostname: s458f154e1f1
  2. IP: 172.27.0.4
  3. # ...

Where to Go Next?

Now that you have a basic understanding of how Traefik can automatically create the routes to your services and load balance them, it is time to dive into the documentation and let Traefik work for you!