Medium,  on  Containers Submissions: 19/94

Internally, container images have a layered structure - some layers represent filesystem diffs, some represent configuration changes, and some represent metadata. However, when a container is created from an image, its filesystem already looks like a regular Linux directory structure. Usually, it's a responsibility of the runtime to mount the image as a container fs, but sometimes, a need to manually extract image contents into a local folder may arise. In particular, this may be useful for debugging purposes.

Layered container images vs. traditional filesystems.

In this challenge, you will need to unpack the filesystem of a container image into a local directory. Make sure you don't use docker save - it dumps the original layered structure of the image!

The image is already pulled for you - you can find it in the output of the docker images command. Store its filesystem in the /root/imagefs directory. Ah, and the image is not really runnable, so you may need to be a bit creative.

Hint 1 💡

Feeling lost? Check out this short tutorial - How To Extract Container Image Filesystem Using Docker.

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