DevOps · Containers · Beginner

Docker Fundamentals

Learn containers from first principles, then build, network, persist, secure and operate them. The course contains 12 complete modules, a guided lab in every module, a Compose capstone and a 35-minute randomized assessment.

Start module 01 Take assessment DevOps learning path

Start with the problem

Package the application, not the machine.

Docker gives teams a repeatable image artifact that carries application filesystem content and runtime metadata, then creates isolated containers from that image wherever Docker is available.

Traditional drift

Recreate each server

Host A: runtime v1 + config A
Host B: runtime v2 + config B
Host C: missing dependency

Application behavior changes when machines are configured differently.

Container image

Promote one artifact

Image: gnu-app:1.0
   ├─ Container A
   ├─ Container B
   └─ Container C

The same image can create many replaceable runtime instances.

Architecture in one minute

CLI → Docker Engine → container runtime.

CLIENTdocker CLI / API client

API

DOCKER ENGINEimages · containers · networks · volumes

RUN

CONTAINERisolated application process

The fundamentals course focuses on observable Docker behavior and workflows rather than internal runtime implementation details.

Course modules

Build the mental model, then operate it.

Every module includes objectives, conceptual explanation, worked commands, an end-to-end lab, expected results, troubleshooting guidance and a knowledge check.

Containers and Docker

Understand the problem containers solve, how containers differ from virtual machines, and where Docker Engine fits in the application lifecycle.

Open module →02

Install, verify and manage the lifecycle

Verify a supported Docker installation, understand how the CLI talks to Engine, and practice create, start, stop, restart, inspect, logs, exec and remove operations.

Open module →03

Images, tags and registries

Understand image references, tags, digests, layers, pulls and pushes so you can reason about exactly what artifact is running.

Open module →04

Dockerfile fundamentals

Write a clear Dockerfile, understand build context and common instructions, and build your first custom application image.

Open module →05

Build cache and image quality

Make builds faster and images safer by controlling build context, cache invalidation, dependency ordering and final image contents.

Open module →06

Container networking and published ports

Understand bridge networks, service discovery, container-to-container communication and the difference between container ports and host publishing.

Open module →07

Persistent storage: volumes, bind mounts and tmpfs

Choose the right storage mechanism and prove why container writable layers should not be treated as durable application data.

Open module →08

Runtime configuration and environment

Separate image contents from environment-specific configuration using environment variables, files, mounts and safe secret-handling principles.

Open module →09

Docker Compose fundamentals

Define a multi-container application declaratively with services, networks, volumes, environment and lifecycle commands.

Open module →10

Health, resources and observability

Operate containers with logs, health checks and resource awareness instead of assuming a running process is a healthy service.

Open module →11

Container security fundamentals

Reduce attack surface with trusted images, least privilege, non-root processes, capability control, read-only data paths and careful Docker socket handling.

Open module →12

Troubleshooting and Compose capstone

Use a repeatable troubleshooting method and assemble the course concepts into a small multi-service Compose project.

Open module →

Prerequisites

Linux basics help; container experience is not required.

Learners should be comfortable in a terminal and understand files, processes and basic networking. Docker installation is verified in the course.

Linux command line

Recommended. You will use shell commands, files and ports throughout the labs.

Networking basics

Helpful. The course explains published ports, container networks and service discovery.

Programming

Not required. Labs use small configuration files and standard container images.

Knowledge assessment

Prove you can reason about containers.

The assessment selects 30 questions from an 84-question bank covering concepts, lifecycle, images/builds, networking, storage, Compose, operations, security and troubleshooting. Pass mark: 75%. Time limit: 35 minutes.

12 MODULES→30 RANDOM QUESTIONS · 35 MIN→PASS ≥ 75%→OPTIONAL CERTIFICATION

Maximum two attempts per 24 hours. Learning and assessment are free. A passing result enables the optional ₹499 GST-inclusive Certificate of Successful Completion pathway.

Course capstone

Build and operate a Compose stack.

Module 12 combines a custom nginx image, a Redis service, health checks, private service discovery, a persistent named volume and controlled teardown into one reproducible project.

Dockerfile→Image→Compose→Network→Volume→Health