failed to unpack: gzip: invalid header

[IvanovOleg]

There is a strange behavior with my custom image:
/usr/lib64/systemd/system-generators/torcx-generator[511]: time="2018-06-04T08:52:05Z" level=error msg="failed to unpack: gzip: invalid header" image=docker-custom reference=com.coreos.cl
It happens if I create archive like this:

archive.tgz:
  bin/
  ./torcx

When I add an extra dir like this:

archive.tgz:
  docker-custom/
     bin/
     .torcx/

generator extracts it fine but with this extra dir in path. How to fix it? Is there any guide how to prepare images?
b.t.w. I can extract both archives using tar without issues

[lucab]

Can you share the image somewhere? How are you packing that?

[IvanovOleg]

@lucab I took the docker:18.05.torcx.tgz image from /usr/share/torcx/store, extracted it, updated the containerd binaries and created a new archive using tar -cvf docker:18.99.torcx.tgz /path/to/dir, made symlink docker-custom:com.coreos.cl.torcx.tgz to it.

[lucab]

@IvanovOleg try with tar -czvf ..., the archive you created is likely a plain non-gzipped tar, thus the error. A file run on it should be able to confirm that.

[IvanovOleg]

@lucab Yes, that fixed an issue. According to the log vendor images propagated it's binaries first and then docker-custom propagated it's binaries, but in /run/torcx/bin links point to the docker binaries, not docker-custom binaries. Do you know why?

[lucab]

You should not have two images trying to expose the same binary at the same time. First disable the one you don't need.

[IvanovOleg]

@lucab Thanks!