📅 Day 1 of My Docker Sprint

👋 Introduction

Today, I officially began my 4-week Docker sprint — a commitment to learn in public, document everything I build, and share each challenge and win with the DevOps community.

But before jumping into commands, I wanted to step back and understand:
Why was Docker even created? What problems was it solving?
Let’s talk about the evolution that led to containers.

🛠️ The Evolution of Deployment

🧱 1. Bare Metal (The Old Days)

In early days, teams ran their apps directly on physical servers (bare metal). Each server ran one OS and hosted apps directly on it.

🚨 Problems:

Wasted resources
Scaling meant buying more machines
If one app crashed the OS, the whole system was down

💽 2. Virtual Machines (VMs to the Rescue)

Then came VMs — we could run multiple OSs on a single server using hypervisors like VMware, VirtualBox, or KVM.

💡 Example: You could run Ubuntu, CentOS, and Windows all on one host.

✅ Benefits:

Better resource usage
OS-level isolation
Easier testing and staging environments

🚨 But still had issues:

Heavyweight (entire OS per VM)
Slow startup times
Difficult to scale quickly

🐳 3. Containers (Docker Enters the Chat)

In 2013, Docker changed everything by introducing lightweight containers — isolated environments that share the host OS but run independently.

✅ Why It Was a Game-Changer:

Fast to spin up
Lightweight (no OS per container)
Portable: “It works on my machine” became irrelevant
Dev & Prod parity

🔍 So What Problem Does Docker Solve?

Problem	Docker's Solution
"Works on my machine"	Same container runs anywhere
App dependency chaos	Package everything in one container
Slow deploys with VMs	Containers start in seconds
Dev/QA/prod differences	Same image used across environments

Docker brought consistency, speed, and simplicity to app delivery. That’s why it’s everywhere — from startups to cloud-native giants.

🐳 What I Did Today

✅ Installed Docker
✅ Ran my first container: docker run hello-world
✅ Read about how Docker actually works
✅ Set up my workspace for the upcoming weeks (Hashnode, GitHub, Notion)

💻 My First Docker Command

docker run hello-world

🧠 What it does:

Pulls the official image from Docker Hub
Spins up a container from it
Executes a simple app that prints a welcome message

❌ Mistakes I Made

Forgot to start Docker engine 😅
Didn’t use sudo the first time (on Linux)
Thought containers were like VMs — but they’re lighter and faster

📅 What’s Next (Day 2 Plan)

Tomorrow I’ll explore the Docker CLI in depth:

docker ps, images, rm, stop, pull, run
Managing and inspecting containers
Understanding lifecycle and cleaning up resources

🧠 Final Thoughts

Understanding why Docker exists made everything clearer today. It’s not just a trendy tool — it’s a solution to real infrastructure problems we’ve battled for years.

This is just Day 1.
If you’re learning too, let’s connect and build together 🚀

📝 Daily updates → abdulraheem.hashnode.dev
📢 Weekly recaps → LinkedIn
🔧 GitHub projects → Coming soon

🔖 Tags

#Docker #DevOps #Containers #LearnInPublic #BuildInPublic #CloudEngineering #Hashnode

🚀 Docker Demystified: Why Every DevOps Engineer Needs It