Docker Containerization Docker Compose and Multi-Container Applications 4

Question 1

What is the role of the COMPOSE_PROJECT_NAME environment variable?

Accepted Answer

Sets the prefix used for naming containers, networks, and volumes

Answer

COMPOSE_PROJECT_NAME sets the project name prefix applied to all resource names, allowing multiple isolated Compose stacks on the same host.

Question 2

In Docker Compose, what distinguishes a 'named volume' from a 'bind mount'?

Accepted Answer

Named volumes are managed by Docker and persist independently of the host path

Answer

Named volumes are created and managed by Docker in its own storage area, while bind mounts reference a specific host filesystem path.

Question 3

How do you view real-time logs from all services in a running Docker Compose application?

Accepted Answer

docker compose logs -f

Answer

docker compose logs -f streams logs from all services in real time, similar to tail -f.

Question 4

What does the 'profiles' feature in Docker Compose allow you to do?

Accepted Answer

Selectively activate groups of services for different environments

Answer

Profiles let you mark services with a profile name so they only start when that profile is explicitly activated via --profile flag.

Question 5

When using Docker Compose with 'docker compose exec', what does this command do differently than 'docker compose run'?

Accepted Answer

exec runs a command in an already running container; run starts a new container

Answer

docker compose exec runs a command inside an already running container, while docker compose run starts a fresh container for a one-off command.

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