Installing Portainer in Docker Swarm: A Step-by-Step Guide

Portainer is an essential tool for managing your Docker environments, offering a simple yet powerful UI for handling containers, images, networks, and more. Integrating Portainer into your Docker Swarm enhances your cluster’s management, making it more efficient and user-friendly. Here’s a concise guide on installing Portainer within a Docker Swarm setup, leveraging the power of NFS for persistent data storage.

Prerequisites

• A Docker Swarm cluster is already initialized.
• NFS server is set up for persistent storage (in this case, at 192.168.0.220).

Step 1: Prepare the NFS Storage

Before proceeding with Portainer installation, ensure you have a dedicated NFS share for Portainer data:

1. Create a directory on your NFS server (192.168.0.220) that will be used by Portainer: /data/portainer/data.
2. Ensure this directory is exported and accessible by your Swarm nodes.

Step 2: Create the Portainer Service

The following Docker Compose file is designed for deployment in a Docker Swarm environment and utilizes NFS for storing Portainer’s data persistently.

version: '3.2'

services:
  agent:
    image: portainer/agent:latest
    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-ee:latest
    command: -H tcp://tasks.agent:9001 --tlsskipverify
    ports:
      - "9000:9000"
      - "8000:8000"
    volumes:
      - type: volume
        source: portainer_data
        target: /data
        volume:
          nocopy: true
    networks:
      - agent_network
    deploy:
      mode: replicated
      replicas: 1
      placement:
        constraints: [node.role == manager]

networks:
  agent_network:
    driver: overlay
    attachable: true

volumes:
  portainer_data:
    driver: local
    driver_opts:
      type: nfs
      o: addr=192.168.0.220,nolock,soft,rw
      device: ":/data/portainer/data"

Step 3: Deploy Portainer

To deploy Portainer, save the above configuration to a file named portainer-agent-stack.yml. Then, execute the following command on one of your Swarm manager nodes:

docker stack deploy -c portainer-agent-stack.yml portainer

This command deploys the Portainer server and its agent across the Swarm. The agent provides cluster-wide visibility to the Portainer server, enabling management of the entire Swarm from a single Portainer instance.

Step 4: Access Portainer

Once deployed, Portainer is accessible via http://<your-manager-node-ip>:9000. The initial login requires setting up an admin user and password. After logging in, you can connect Portainer to your Docker Swarm environment by selecting it from the home screen.

Conclusion

Integrating Portainer into your Docker Swarm setup provides a robust, web-based UI for managing your cluster’s resources. By leveraging NFS for persistent storage, you ensure that your Portainer configuration and data remain intact across reboots and redeployments, enhancing the resilience and flexibility of your Docker Swarm environment.