Is it possible to load balance MQTT traffic with Traefik 2.0 TCP feature?

Question

I am currently using Haproxy to load balance MQTT traffic to N dockerized mqtt brokers

Traefik 2.0 is out and can proxy TCP traffic, I am wondering if it is possible to load balance MQTT traffic to N dockerized mqtt brokers using Traefik as load balancer like you would do with Haproxy.

I tried some basic configuration using the official traefik doc, but i can't get the traffic upstream.

Has anyone tried this already?

Answer 1

Yes I did it yesterday. I used the VerneMQ for MQTT broker and Traefik as a load balancer. The following configurations file are for Docker Swarm.

Here is the docker-compose configuration I use:

version: "3"

services:
    traefik:
        image: traefik:v2.1
        ports:
            - "80:80"
            - "1883:1883"
        volumes:
            - /var/run/docker.sock:/var/run/docker.sock
            - /dev/random:/dev/random
            - ./traefik.toml:/traefik.toml
        deploy:
            placement:
                constraints: [node.role == manager]
            labels:
                - traefik.enable=true
                - traefik.docker.network=net

                - traefik.http.routers.dashboard.rule=Host(`traefik.home.gtheofilis.com`)
                - traefik.http.routers.dashboard.entrypoints=http
                - traefik.http.routers.dashboard.service=api@internal
                - traefik.http.services.dashboard.loadbalancer.server.port=9999

    vmq0:
        image: vernemq/vernemq
        environment:
            DOCKER_VERNEMQ_SWARM: 1
            DOCKER_VERNEMQ_ACCEPT_EULA: "yes"
            DOCKER_VERNEMQ_ALLOW_ANONYMOUS: "on"
        deploy:
            placement:
                constraints: [node.role == manager]
            labels:
                - traefik.enable=false

    vmq:
        image: vernemq/vernemq
        depends_on:
            - vmq0
        environment:
            DOCKER_VERNEMQ_SWARM: 1
            DOCKER_VERNEMQ_DISCOVERY_NODE: vmq0
            DOCKER_VERNEMQ_ACCEPT_EULA: "yes"
            DOCKER_VERNEMQ_ALLOW_ANONYMOUS: "on"
        deploy:
            replicas: 3
            labels:
                - traefik.enable=true
                - traefik.docker.network=net
                - traefik.tcp.routers.mqtt.rule=HostSNI(`*`)
                - traefik.tcp.routers.mqtt.entrypoints=mqtt
                - traefik.tcp.services.mqtt.loadbalancer.server.port=1883

                - traefik.http.routers.mqtt_dashboard.rule=Host(`vernemq.home.gtheofilis.com`)
                - traefik.http.routers.mqtt_dashboard.service=mqtt_dashboard
                - traefik.http.routers.mqtt_dashboard.middlewares=auth
                - traefik.http.routers.mqtt_dashboard.entrypoints=http
                - traefik.http.services.mqtt_dashboard.loadbalancer.server.port=8888

networks:
    default:
        external:
            name: net

And this is my traefik.toml configuration file:

[api]
    dashboard = true

[entryPoints]
  [entryPoints.http]
    address = ":80"
  [entryPoints.mqtt]
    address = ":1883"

[providers]
    [providers.docker]
        endpoint = "unix:///var/run/docker.sock"
        swarmMode = true