DevOps Roadmap 2026: Zero to Hero (Linux, AWS, K8s, CI/CD, Terraform, Docker & GitHub Actions) - Dockerfile Tutorial 2026: How to use FROM, WORKDIR, RUN, COPY & CMD Instructions

Dockerfile Tutorial 2026: How to use FROM, WORKDIR, RUN, COPY & CMD Instructions Stop using random images and start building your own! In Chapter 13 of our DevOps Roadmap 2026, we move into one of the most critical skills for any DevOps Engineer: Writing Dockerfiles. If you want to automate your deployments and containerize your own applications, you must master these instructions. In this tutorial, we break down the "building blocks" of a Docker Image. We’ll show you how to select a base image with FROM, set your environment with WORKDIR, execute commands during the build with RUN, move your code with COPY, and finally, define how your app starts with CMD. No more "black box" containers—after this video, you'll know exactly how to architect a lightweight, secure, and production-ready Docker image. 🚀 What We Cover in This Chapter: 🔥 The Foundation: Choosing the right base image with FROM 🏗️ 🔥 Organization: Why you should always use WORKDIR 📂 🔥 The Build Phase: Running shell commands with RUN ⚡ 🔥 Code Injection: How to properly use COPY vs ADD 📤 🔥 The Entry Point: Defining the default execution with CMD 🎬 🔥 Best Practices: Writing clean Dockerfiles for 2026 🛡️ 🛠️ Chapter 13 Toolkit & Resources Ready to build your first image? Access the source code and the step-by-step guide below to follow along with the lab: 🔗 GitHub Repository (SharksNode): https://github.com/faisikhan/sharksnode/ ⏱️ Navigate the Dockerfile Masterclass: 00:00 🎬 Introduction: What is a Dockerfile & Why do we need it? 03:37 📝 The Blueprint: How to write a Dockerfile (Step-by-Step) 05:15 🏗️ Deep Dive: Understanding Docker Image Layers & Caching 20:07 🧪 Hands-on Lab: Building your first Docker Image from scratch 50:14 🌐 Real-World Example: Building an NGINX Web Server Image 🚀 Level Up Your DevOps Career (Free Full Courses) Master the most in-demand tools with these comprehensive guides: ☁️ Cloud Certifications 🔸 AWS AI Practitioner (AIF-C01): https://youtu.be/3Ntb6S4xhDQ 🔸 AWS Cloud Practitioner (CLF-C02): https://youtu.be/plJ6h8PdIMU 🔸 Azure Fundamentals (AZ-900): https://youtu.be/wmaLT35typw ☸️ Containers & Orchestration 🔸 Kubernetes Mastery: https://youtu.be/jZ7lwcPLA1M 🔸 Docker for Beginners: https://youtu.be/KZvMdsg8KTY 🛠️ Automation & Infrastructure (IaC) 🔸 Terraform Full Course: https://youtu.be/lWUhTLWMijY 🔸 CI/CD Pipeline Projects: https://youtu.be/XpzdE_PJQLE 🐧 Essential Fundamentals 🔸 Linux for DevOps: https://youtu.be/McqQ5n0FyjM 🔸 Git & GitHub Tutorial: https://youtu.be/hshvdd4dtqo 🌐 Join the DevOps Molvi Community! 🔹 LinkedIn: https://www.linkedin.com/in/faisikhan/ 🔹 Instagram: https://www.instagram.com/DevOpsMolvi 🔹 Facebook: https://www.facebook.com/devopsmolvi 🔹 TikTok: https://www.tiktok.com/@devopsmolvi Enjoyed the video? 🚀 Don't forget to Like, Subscribe, and hit the Bell icon to never miss a cloud tutorial! #Dockerfile #DevOpsRoadmap #DockerTutorial #Containerization #DevOps2026 #LearnDocker #WebDevelopment #NGINX #GitHub #devopsmolvi