====== docker executor ======

===== use of closed network connection =====
Docker image creation in CI job. Build kit enabled.

<code>
The push refers to repository [gitlab.example.com:5050/xxx/yyy/zzz]
10c2aa743a1a: Waiting
ce6021a72f8a: Preparing
...
d7987a0357ee: Retrying in 5 seconds
d0de3ca27f7d: Retrying in 5 seconds
...
d0de3ca27f7d: Retrying in 19 seconds
698c6cbaebf1: Retrying in 19 seconds
...
...
698c6cbaebf1: Retrying in 1 second
b30c875acc0a: Retrying in 1 second
343b0b7537a2: Waiting
write tcp 192.168.0.138:58472->192.168.0.42:5050: use of closed network connection
Command exited with non-zero status 1
ERROR: Job failed: exit code 1
</code>

Gitlab's registry log file shows:
<file log /var/log/gitlab/registry/current>
level=warning msg="client disconnected during blob PATCH" copied=64136 43 error="unexpected EOF" go_version=go1.16.9 
level=error msg="connection reset by peer" code=CONNECTIONRESET detail="client disconnected" error="connectionreset: connection reset by peer" go_version=go1.16.9
</file>

Retrying job on the same runner also fails.
Possible solution: remove cached image on runner host to force recreation of layers.

  * [[https://github.com/moby/moby/issues/16959|Error Pushing to Docker Hub, several errors: EOF, use of closed network connection, #16959]]
  * [[https://github.com/moby/moby/issues/16949|Docker push fails with EOF in private registry 2.0 behind NGINX Proxy #16949]]