Docker Terminal Simulator
Practice Docker commands in an interactive browser terminal. Learn images, containers, logs, exec, Dockerfile builds, volumes, networks, and Docker Compose with a live Docker daemon visualization.
Category: DevOps
Topics covered: docker, containers, terminal, devops, compose, networking, volumes, educational, interactive
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Docker Terminal Simulator
Practice Docker commands in an interactive browser terminal. Learn images, containers, logs, exec, Dockerfile builds, volumes, networks, and Docker Compose with a live Docker daemon visualization.
Docker Terminal Lab
Practice real Docker CLI workflows in a safe browser simulator. Run containers, inspect logs, build images, wire up networks, persist data with volumes, and manage a Compose stack without needing a local Docker daemon.
Start by checking the Docker client and server versions.
Welcome to Docker Terminal Lab.
Type "help" for available commands, or follow the current task.
docker psRunning containers
docker logs webRead stdout/stderr
docker exec web shRun inside a container
docker compose up -dStart a stack
hello-world:latest13.3kBMinimal image that proves Docker can pull and run containers.
alpine:3.197.4MBTiny Linux base image often used for containers.
No named volumes yet.
About this Docker simulator
What you'll learn
- How the Docker CLI talks to a local daemon
- The difference between images, containers, layers, and tags
- Container lifecycle commands: run, ps, logs, stop, start, exec, inspect
- How port publishing connects host traffic to container processes
- Why volumes and user-defined networks matter for stateful apps
- How Docker Compose coordinates a multi-container stack
Key commands covered
- Basics: docker version, docker info, docker images
- Containers: docker run, ps, logs, stop, start, exec, inspect
- Builds: Dockerfile, docker build, docker history
- State: docker volume, docker network, docker compose
Browser-safe by design
This lab does not run real containers. It models Docker daemon state in the browser so you can safely practice commands, understand cause and effect, and build muscle memory before using Docker on your machine or in CI.
Why learn Docker?
- Docker packages apps with their runtime dependencies.
- Containers make local development, CI, and production deployments more consistent.
- Docker fundamentals transfer directly to Kubernetes and cloud container platforms.
Overview
This Docker simulator is a browser terminal where you practice the commands you use every day without installing Docker or risking a real host. Six lessons take you from the basics to a small application. Docker daemon basics covers docker version and docker info, pulling an image and listing what is stored locally. Container lifecycle covers running a container in the background, listing it, reading its logs, stopping it and starting it again. Debugging containers covers exec and inspect. Build images covers reading a Dockerfile, building and tagging an image and checking its layer history. Data and networking covers named volumes such as pgdata and user-defined bridge networks such as appnet, and why containers on the same network can reach each other by name. Compose workflow brings it together with docker compose up -d, ps and down for a two-service app. Each command is checked as you type it, the output looks like what Docker prints, and your progress is tracked per lesson, so you build muscle memory for the flags that matter, like -d, -p, -v, --name and --network.
Try this
- Work through "Container lifecycle" to run nginx in the background on port 8080, read its logs, stop it and start it again.
- Open "Data & Networking" to create the appnet network and pgdata volume and run a database container that uses both.
- Finish with "Compose workflow" and bring the two-service app up and down with docker compose.
Frequently asked questions
- What is the difference between docker run and docker start?
- docker run creates a new container from an image and starts it. docker start starts an existing container that was stopped, keeping its configuration and writable layer.
- How do containers talk to each other in Docker?
- Put them on the same user-defined network. Docker provides DNS on that network, so a container can reach another one by its name, for example db:5432.
- What is a Docker volume?
- Storage managed by Docker that lives outside the container writable layer, so data such as a database survives when the container is removed and recreated.
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