docker save exports only 18K tar for deepseekv41-flash-0909 (no layer blobs) #955

Summary

docker save vllm/vllm-openai:deepseekv41-flash-0909 produces an 18KB tar containing only manifest/config, no actual layer data. Other vLLM images on the same host export fine.

Environment
Docker 29.7.2, storage driver: overlayfs (containerd snapshotter)
Ubuntu 22.04
Repro

docker pull vllm/vllm-openai:deepseekv41-flash-0909
docker save -o bad.tar vllm/vllm-openai:deepseekv41-flash-0909
ls -lh bad.tar  # 18K

Workaround

docker build -t fixed -<<EOF
FROM vllm/vllm-openai:deepseekv41-flash-0909
EOF
docker save -o good.tar fixed  # works (several GB)

Question

Is this image published as a manifest list? Any non-standard layer media types? This breaks offline deployment workflows.