Backup and restore strategies in Docker - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the main purpose of backup in Docker environments?

Backup in Docker environments is to save copies of important data, such as container volumes or images, so you can restore them if something goes wrong.

beginner

How can you backup a Docker volume?

You can backup a Docker volume by creating a temporary container that mounts the volume and copies its data to a safe location outside Docker.

beginner

What command can you use to save a Docker image as a file for backup?

Use docker save <image_name> -o <file_name>.tar to save a Docker image to a tar file.

beginner

What is a simple way to restore a Docker volume from a backup?

Create a temporary container that mounts the volume and copies the backup data into it, replacing the old data.

intermediate

Why is it important to regularly test your Docker backup and restore process?

Testing ensures your backups work and you can recover data quickly when needed, avoiding surprises during real failures.

Which command saves a Docker image to a file?

A docker save

B docker backup

C docker export

D docker commit

docker save saves an image to a file. docker export exports a container's filesystem, not an image.

How do you backup data stored in a Docker volume?

A Export the volume directly

B Use docker save on the volume

C Use docker commit on the volume

D Copy data from the volume using a temporary container

Volumes are backed up by copying their data using a temporary container that mounts the volume.

What is the purpose of the docker load command?

A Backup a Docker volume

B Restore a Docker image from a saved file

C Start a new container

D Remove an image

docker load restores an image from a tar file saved by docker save.

Which of these is NOT a good backup strategy for Docker data?

A Ignoring backups because Docker is fast to rebuild

B Saving images to files

C Testing restore procedures often

D Regularly copying volume data to safe storage

Ignoring backups is risky. Even if Docker is fast to rebuild, data loss can be critical.

What is a key step after restoring Docker data from backup?

A Restart the Docker daemon

B Delete the backup files immediately

C Verify the data is intact and containers work correctly

D Rebuild all images

Always verify restored data to ensure your system works as expected.

Explain how to backup and restore a Docker volume step-by-step.

Think about using a container as a helper to access volume data.

Describe why testing backup and restore processes is important in Docker environments.

Consider what happens if you never check your backups.