Multi-stage copy of everything in an image fails after version 2.4.0.0 (earlier versions work)

Docker Desktop
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1

I have an example docker build - a Dockerfile that looks like the following:

FROM debian:buster-slim as other
FROM alpine:latest
COPY --from=other / /

This builds successfully prior to the 2.4.0.0 version of docker desktop for windows. Attempting to build with any version 2.4.0.0 and newer results in the following style of copy error:

 => ERROR [stage-1 2/2] COPY --from=other / /                                                                      1.0s
------
 > [stage-1 2/2] COPY --from=other / /:
------
failed to solve with frontend dockerfile.v0: failed to build LLB: cannot replace to directory /var/lib/docker/overlay2/hc1w3xu51id4vm10bbsijznxa/merged/var/lock with file

Does anyone know of a work-around for this style of whole image copy over an existing image to work in docker desktop for Windows versions 2.4.0.0+?

Note also the above is just a useless example to illustrate the issue with small images - I have a real scenario where I am copying an entire distroless image right over the top of the equivalent distroā€™d image in order to restore package managers where this whole image copy is useful.

Any help is much appreciated.

1 Like
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Go to settings, then Docker Engine and change ā€œbuildkit: trueā€ to ā€œbuildkit: falseā€. Buildkit is a useful feature but there are some things you cannot the with it. I donā€™t know if it is intentional in this case but disabling buildkit solved it for me.

If you donā€™t want to disable it globally, then you can disable it in powershell temporarily

$env:DOCKER_BUILDKIT=0
docker build ...
2 Likes
3

Thank you very much @rimelek - yes, disabling build-kit worked like a charm!