Copying files to and from containers in Docker - Cheat Sheet & Quick Revision

Recall & Review

beginner

What command copies files from your local machine to a Docker container?

Use docker cp <local_path> <container_id>:<container_path> to copy files from your local machine to a container.

beginner

How do you copy files from a Docker container to your local machine?

Use docker cp <container_id>:<container_path> <local_path> to copy files from a container to your local machine.

beginner

Can you copy directories using docker cp?

Yes, docker cp supports copying entire directories between your local machine and containers.

intermediate

What happens if the destination path does not exist when copying files with docker cp?

Docker will create the destination directory if it does not exist when copying directories. For files, the parent directory must exist.

intermediate

Is it possible to copy files between two running containers directly using docker cp?

No, docker cp works only between your local machine and a container. To copy between containers, copy to local first, then to the other container.

Which command copies a file named app.log from your local machine to the /var/log directory inside a container with ID abc123?

A docker cp app.log abc123:/var/log

B docker copy app.log abc123:/var/log

C docker transfer app.log abc123:/var/log

D docker move app.log abc123:/var/log

The correct command is docker cp followed by the source and destination paths.

To copy a directory named data from a container xyz789 to your local machine, which command is correct?

A docker copy xyz789:/data ./data

B docker cp ./data xyz789:/data

C docker cp xyz789:/data ./data

D docker cp data xyz789:/data

Use docker cp container_id:/path local_path to copy from container to local.

What will happen if you try to copy a file to a container path that does not exist?

A Docker will create the path and copy the file

B The command will fail with an error

C Docker will overwrite the container

D The file will be copied to the container root directory

Docker requires the parent directory to exist when copying files; otherwise, the command fails.

Can you use docker cp to copy files directly between two running containers?

A No, you must copy files to local first

B Yes, by specifying both container IDs

C Yes, but only for files smaller than 10MB

D No, copying files is not supported by Docker

docker cp only works between local machine and a container.

Which of these is NOT a valid use of docker cp?

A Copying a file from local to container

B Copying a file from container to local

C Copying a directory from container to local

D Copying files between two containers directly

Direct copying between containers is not supported by docker cp.

Explain how to copy a file from your local machine into a running Docker container.

Think about source and destination order in the command.

Describe the steps to copy a directory from a Docker container to your local machine.

Remember the order: container path then local path.