buildctl fails on Windows with "archive/tar: invalid tar header"

[TinaMor]

Description

buildctl fails on Windows with "archive/tar: invalid tar header" for both type=oci and type=docker using CMD or PowerShell.

> buildctl.exe build --progress=tty --frontend=dockerfile.v0 --local=context=. --output=type=docker,name=test/hello-buildkit,push=false --local=dockerfile=./ --opt=filename=Dockerfile | docker load

archive/tar: invalid tar header
error: failed to solve: failed to copy to tar: rpc error: code = Unknown desc = write /dev/stdout: The pipe is being closed.

Test Dockerfile

FROM mcr.microsoft.com/windows/nanoserver:ltsc2022   
RUN echo "hello"

Additional info

Using --progress plain works

> buildctl.exe build --progress=plain --frontend=dockerfile.v0 --local=context=. --output=type=docker,name=test/hello-buildkit,push=false --local=dockerfile=./ --opt=filename=Dockerfile | docker load

#1 [internal] load build definition from Dockerfile
#1 transferring dockerfile: 108B done
#1 DONE 0.0s

#2 [internal] load metadata for mcr.microsoft.com/windows/nanoserver:ltsc2022
#2 DONE 0.3s

#3 [internal] load .dockerignore
#3 transferring context: 2B done
#3 DONE 0.0s

#4 [1/2] FROM mcr.microsoft.com/windows/nanoserver:ltsc2022@sha256:be37c9e8bf388c4e3ef27b4a2592b94adab551e231644ce3c9d4d3dc0a50af41
#4 resolve mcr.microsoft.com/windows/nanoserver:ltsc2022@sha256:be37c9e8bf388c4e3ef27b4a2592b94adab551e231644ce3c9d4d3dc0a50af41 0.0s done
#4 DONE 0.0s

#5 [2/2] RUN echo "hello"
#5 CACHED

#6 exporting to docker image format
#6 exporting layers done
#6 exporting manifest sha256:5beace3848b86d36f96ada17197ca4558cb4ae79608610094cc878529bb578d7 0.0s done
#6 exporting config sha256:72a13ebdd2882395f1acaa8af867ed4d48993d7cd153a566aa135f12c96efeb4 0.0s done
#6 sending tarball
#6 sending tarball 4.2s done
#6 DONE 4.2s
afe057336777: Loading layer [==================================================>]  116.9MB/116.9MB
35185b6eab61: Loading layer [==================================================>]  73.08kB/73.08kB
Loaded image: test/hello-buildkit:latest

Environment

1. Windows
   ProductName : Windows Server 2022 Datacenter Evaluation
   ReleaseId : 2009
   CurrentBuild : 20348
   DisplayVersion : 21H2
2. buildctl
   buildctl github.com/moby/buildkit v0.17.1 8b1b83e
3. Containerd
   containerd github.com/containerd/containerd/v2 v2.0.0 207ad711eabd375a01713109a8a197d197ff6542
4. docker
   Version 27.3.1
   

[TinaMor]

May be caused by https://github.com/containerd/console: https://github.com/containerd/console/issues/83

[profnandaa]

What do you get on the CMD shell?

[TinaMor]

Same error:

> C:\Windows\System32>buildctl.exe build --progress=tty --frontend=dockerfile.v0 --local=context=. --output=type=oci,name=test/hello-buildkit,push=false --local=dockerfile=./ --opt=filename=Dockerfile | docker load

archive/tar: invalid tar header
error: failed to solve: failed to copy to tar: rpc error: code = Unknown desc = write /dev/stdout: The pipe is being closed.

[modaiwang]

i have seen the same problem in windows docker environment (within vmware), do you have any new solutions?

[ngebremariam-msft]

The reason for getting "archive/tar: invalid tar header" when running on PowerShell or CMD is because of the commands that are chained together during the build.

 --progress=tty  → requires a live terminal (an interactive console window, i.e. output going straight to the screen, not into a pipe or file). Because of that, if you try to write a tar file and load it at the same time (piping to docker load), you get "failed to get console: The handle is invalid" from buildctl, or "archive/tar: invalid tar header" from docker. It's essentially the same problem seen from two different sides: buildctl fails right away and prints a short error message instead of building the image, and that error text gets passed down the pipe to docker load, which was expecting an image (a tar file). Since it received a bit of error text instead of a tar, it reports the tar as invalid.

Workarounds

Default:
Continue to use --progress=plain or --progress=auto (these don't need a terminal, so you can keep piping to docker load).

Fix:
Write the tar to a file, then load it (two steps, no pipe):

buildctl.exe build --progress=tty --frontend=dockerfile.v0 --local=context=. --output=type=docker,name=test/hello-buildkit,push=false,dest=out.tar --local=dockerfile=./ --opt=filename=Dockerfile

docker load -i out.tar

[thaJeztah]

The fix in containerd/console mentioned above may also help (once shipped); progress normally is meant to be printed on STDERR, but on windows unconditionally was put on STDOUT (which is the stream that's piped here);

• windows: delegate Read, Write, Fd, Name to the file passed to newMaster containerd/console#88