Docker for Edge and IoT

Docker for Edge and IoT

Introduction

Your team has a Raspberry Pi running Mosquitto, Node-RED, and a small database. Installing everything by hand on each board is fragile — versions drift, dependencies conflict, and "it worked on my laptop" returns.

Docker packages an application and its dependencies into an image you run as a container — isolated, repeatable, easy to redeploy. For embedded engineers, Docker is less about the MCU firmware and more about the gateway and cloud edge: the Linux box next to your robots.

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Core concepts

Term	Meaning
Image	Read-only template (e.g. eclipse-mosquitto)
Container	Running instance of an image
Dockerfile	Recipe to build your own image
Volume	Persistent data outside container filesystem
Port mapping	-p 1883:1883 exposes broker to LAN
Docker Compose	YAML file defining multi-container stacks

In plain terms

An image is a frozen lunch box with exact food inside. A container is when you heat and eat one serving — same recipe every time, no surprise missing salt.

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Why embedded/IoT teams use it

Benefit	Example
Reproducible lab	Same Mosquitto + Node-RED stack on every Pi
Isolation	Database crash does not kill broker
Updates	Pull new image tag; roll back if broken
CI/CD	Build gateway services in pipeline

MCUs still flash firmware normally — Docker runs on Linux gateways (Pi, industrial PC, cloud VM).

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Minimal example — MQTT broker

docker run -d --name mosquitto -p 1883:1883 eclipse-mosquitto:2

Devices on the LAN connect to pi-ip:1883. Config and persistence mount via volumes in real projects.

Docker Compose (sketch):

services:
  mosquitto:
    image: eclipse-mosquitto:2
    ports:
      - "1883:1883"
  nodered:
    image: nodered/node-red:latest
    ports:
      - "1880:1880"
    depends_on:
      - mosquitto

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Install paths (pick your machine)

Platform	Notes
Raspberry Pi	Docker Engine for ARM
Windows / macOS	Docker Desktop for development
Linux server	Native engine, common in cloud

Use official install docs for your OS — versions change; concepts stay the same.

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Videos — other ways to learn

Why use Docker

Why Use Docker - Docker Tutorial For Beginners

What is Docker

What is Docker

Docker client basics

Using the Docker Client

What is a container

But Really, What's a Container?

Quick overview

Learn Docker in 12 Minutes

Docker Compose

Docker Compose in 12 Minutes

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Relevant topics

• Node-RED for IoT
• MQTT and IoT messaging
• Operating systems
• Virtualization
• Connectivity architecture

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Starting points

1. Install Docker on your dev machine; run docker run hello-world.
2. Start Mosquitto container; connect with mosquitto_sub from host.
3. Write a two-service docker-compose.yml for broker + Node-RED.
4. Export compose file to Git — teammates reproduce in one command.

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Focus points

• Containers are not VMs — they share the host kernel; understand isolation limits.
• Persist data with volumes — container delete should not wipe MQTT config.
• ARM vs x86 images — Pi needs ARM-compatible tags.
• Secrets — use env files or Docker secrets, not hardcoded passwords in Git.

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Key points

• Docker makes gateway stacks repeatable on Pis and servers.
• Image + container + compose are the vocabulary you need first.
• Pair with Node-RED and MQTT for full IoT lab architecture.