Docker Containerization Docker Compose and Multi-Container Applications 5

Question 1

In a Docker Compose file, what does specifying 'network_mode: host' for a service do?

Accepted Answer

Removes container network isolation so the service shares the host's network stack

Answer

network_mode: host removes network isolation and the container directly uses the host's network interfaces and ports.

Question 2

Which strategy ensures a service in Docker Compose only starts after its dependency is fully healthy, not just running?

Accepted Answer

depends_on with condition: service_healthy

Answer

depends_on with condition: service_healthy waits for the dependency's healthcheck to pass before starting the dependent service.

Question 3

What is the effect of using 'docker compose up -d' followed by 'docker compose stop'?

Accepted Answer

Stops running containers but keeps them and their state preserved

Answer

docker compose stop halts the running containers without removing them, preserving their state so they can be restarted with docker compose start.

Question 4

How can you pass build-time arguments to a Dockerfile from a Docker Compose file?

Accepted Answer

Using 'args' under the 'build' key

Answer

The args sub-key under build passes ARG values to the Dockerfile during the build process.

Question 5

What is the recommended approach for sharing a database volume between a primary and a replica service in Docker Compose?

Accepted Answer

Use the same named volume for both services

Answer

Referencing the same named volume in multiple service definitions allows both services to access the same persisted data storage.

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