Docker swarm Web dashboard with Portainer

Context

Today, a very quick blog post to continue the series of my docker swarm services recipes. If you haven’t, I suggest reading some of my my home lab posts to give you an idea if you don’t already have an understanding of a docker swarm architecture.

Today’s “recipe” is for Portainer. For those living outside the docker world before, Portainer is a web UI to manage docker containers (with or without swarm engine).

As indicated on their website: Portainer¹: > Build and manage your Docker environments with ease today.

In a simple configuration with docker running standalone (meaning not with kubernetes or swarm mode), you can just run the portainer/portainer container on your server, but in a swarm mode, you need to deploy agents on each node that will communicate with portainer server.

Installation

Create directory structure first, if you follow my filesystem structure², just do:

    mkdir /mnt/cluster-data/{containers-data,services-config}/portainer

Then, create the /mnt/cluster-data/services-config/portainer/docker-compose.yml file:

    version: '3'

    services:
      agent:
        image: portainer/agent
        volumes:
          - /var/run/docker.sock:/var/run/docker.sock
          - /var/lib/docker/volumes:/var/lib/docker/volumes
        networks:
          - agent_network
        deploy:
          mode: global
          placement:
            constraints: [node.platform.os == linux]

      portainer:
        image: portainer/portainer
        command: -H tcp://tasks.agent:9001 --tlsskipverify
        ports:
          - 9000:9000
          - 8000:8000 #changeme
        networks:
          - agent_network
        deploy:
          mode: replicated
          replicas: 1
          placement:
            constraints:
              - node.role == manager
        volumes:
          - /mnt/cluster-data/containers-data/portainer/:/data #changeme if you don't use this file structure

    networks:
      agent_network:
        driver: overlay

Important piece are:

• Portainer agent is deployed globally (mode: global), this means that each node will have 1 instance of this container.
• Portainer server is deployed only on manager nodes.
• The constraints is just there to “look good”, because I don’t have anything else than linux platform anyway :p.

Deploy the stack:

    docker stack deploy portainer -c /mnt/cluster-data/services-config/portainer/docker-compose.yml

You can then go to http://<ClusterIPAddress:8000, to create your user and configure portainer (select environment local and then create your user)

And stop it:

    docker stack rm portainer

That’s it for now, I did say it would be a very quick one :).