Practice & Assessment
Test your understanding of Docker Fundamentals
Multiple Choice Questions
5What is the key architectural difference between a Docker container and a virtual machine?
You run `docker rm my-app` after writing files inside that container. What happens to those files?
Which command runs an nginx container in the background and maps host port 9090 to container port 80?
What is the correct use case for a bind mount over a named volume?
A container exits immediately after `docker run ubuntu`. What is the most likely cause?
Coding Challenges
1Run a PostgreSQL container with persistent storage
Using only the Docker CLI (no Compose), run a PostgreSQL 16 container named 'pg-dev' with: (1) a named volume called 'pg-dev-data' mounted at /var/lib/postgresql/data, (2) POSTGRES_PASSWORD set to 'devpass', (3) POSTGRES_DB set to 'appdb', (4) port 5432 mapped to host port 5433. Then verify the container is running with docker ps, connect using `docker exec -it pg-dev psql -U postgres`, run `\l` to list databases and confirm 'appdb' appears. Stop the container, remove it, then re-run the same command and verify data persists. Document the exact commands used. Estimated time: 20 minutes.
Mini Project
Containerized Static File Server
Build a local static file server using Docker. Create a directory called 'site' containing an index.html with your name and a short bio. Run an nginx container that serves this directory using a bind mount mapped to /usr/share/nginx/html, with port 8080 on the host mapped to port 80 in the container. The container must run in detached mode with the name 'static-server'. Verify the site loads at http://localhost:8080. Then edit index.html on the host while the container is running and confirm the change appears without restarting the container. Stop and remove the container, then repeat using a named volume instead of a bind mount — observe the difference in behavior when you try to edit files. Write a short README listing the commands used for each approach.