Running containers in detached mode in Docker - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does running a Docker container in detached mode mean?

Running a Docker container in detached mode means the container runs in the background, allowing you to continue using the terminal without being attached to the container's output.

beginner

Which Docker command option runs a container in detached mode?

The -d option in the docker run command runs the container in detached mode.

beginner

How can you check running containers after starting one in detached mode?

Use the command docker ps to list all running containers, including those started in detached mode.

intermediate

What is the difference between running a container in attached vs detached mode?

Attached mode shows the container's output in the terminal and keeps the terminal busy. Detached mode runs the container in the background, freeing the terminal for other commands.

beginner

How do you stop a container running in detached mode?

You can stop a detached container using docker stop <container_id_or_name>.

Which command runs a Docker container in detached mode?

A docker run --rm nginx

B docker run -it nginx

C docker run -d nginx

D docker run --name nginx

The -d option runs the container in detached mode, so docker run -d nginx is correct.

What does the docker ps command show?

A All running containers

B All stopped containers

C Docker images

D Docker volumes

docker ps lists all currently running containers.

If you want to see the logs of a detached container, which command do you use?

A docker exec <container_id>

B docker attach <container_id>

C docker stop <container_id>

D docker logs <container_id>

Use docker logs <container_id> to view output from a detached container.

What happens if you run a container without -d option?

A Container runs attached to terminal

B Container runs in background

C Container stops immediately

D Container runs with no network

Without -d, the container runs attached to the terminal, showing output and blocking the terminal.

How do you stop a container running in detached mode?

A docker start <container_id>

B docker stop <container_id>

C docker run -d <container_id>

D docker rm <container_id>

Use docker stop <container_id> to stop a running container, including those in detached mode.

Explain what detached mode is in Docker and why you might want to use it.

Think about running a program and still being able to use your computer for other things.

Describe the steps to run a container in detached mode and then check if it is running.

Start with the command to run, then how to verify.