Docker and CI/CD · Junior · Question 72 of 75

How are an image's layers and a container's changes stored?

✓Correct answer: Image layers are read-only; each container has a writable layer
2Containers write their changes straight into the image layers
3Each container gets a full copy of every image layer on start

Explanation

Copy-on-write lets many containers share one image. Changes go into the container's own layer and disappear with it.

Further reading

Docker Docs: Storage drivers and layers ↗

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