Why request the production.cloudflare.docker.com ?

[seepine]

The workflow yml

      - name: Build and push
        uses: docker/build-push-action@v4
        with:
          context: .
          file: ./Dockerfile
          platforms: |
            linux/amd64
            linux/arm64
          push: true
          tags: test:latest

And got the error

 > [linu***/arm64 internal] load metadata for docker.io/library/alpine:latest:
------
Dockerfile:1
--------------------
   1 | >>> FROM alpine
   2 |     CMD echo 'test docker build***!!'
--------------------
ERROR: failed to solve: docker.io/library/alpine: failed to resolve source metadata for docker.io/library/alpine:latest: failed to copy: httpReadSeeker: failed open: failed to do request: Get "https://production.cloudflare.docker.com/registry-v2/docker/registry/v2/blobs/sha256/1d/1d34ffe**190be23d3de5**de0a436676**58f48f835c3a2d**68b798c15a7f1/data?verify=1718641860-garIfCZ**RLgwzS**JFgHb**0VE%3D": read tcp 172.17.0.3:42364->1*7.2*0.8.36:443: read: connection reset by peer

I am using Gitea with Gitea Action in a local network environment. And i have configured a registry mirror, run docker pull alpine is able to fetch the image.
Why does the docker/build-push-action@v4 action need to request from production.cloudflare.docker.com, this leads to build failure.

[seepine]

Q1: Why request the production.cloudflare.docker.com

I config /etc/docker/daemon.json of registry-mirrors and run docker pull nginx:1.25-alpine-slim can work. But docker buildx build throw error.

ERROR: failed to solve: nginx:1.25-alpine-slim: failed to resolve source metadata for docker.io/library/nginx:1.25-alpine-slim: failed to copy: httpReadSeeker: failed open: failed to do request: Get "https://production.cloudflare.docker.com/registry-v2/docker/registry/v2/blobs/sha256/2c/2c84e1e0****5023d558e/data?verify=1723****dPXX9c%3D": dial tcp 31.13.95.48:443: connect: connection refused

Q2: Why cannot use docker proxy ?

I set empty /etc/docker/daemon.json of registry-mirrors, and config /etc/systemd/system/docker.service.d/proxy.conf like this

[Service]
Environment="HTTP_PROXY=http://192.168.1.1:7890/"
Environment="HTTPS_PROXY=http://192.168.1.1:7890/"
Environment="NO_PROXY=localhost,127.0.0.1"

And run docker pull nginx:1.25-alpine-slim can work. But docker buildx build throw error also.

[snowdream]

I think i get the same error.

#2667
docker/build-push-action#1223