Description of problem:

Experiencing spurious errors while pushing images to an OpenShift 3.7 cluster.

Some of the error seen include:

- failed to upload schema2 manifest: received unexpected HTTP status: 500 Internal Server Error - falling back to schema1
- Attempting next endpoint for push after error: received unexpected HTTP status: 500 Internal Server Error
- Attempting next endpoint for push after error: error parsing HTTP 400 response body: unexpected end of JSON input: ""
- Upload failed, retrying: read tcp X.X.X.X:XXXX->Y.Y.Y.Y:443: read: connection reset by peer
- Attempting next endpoint for push after error: Patch https://registry.example.com/v2/XXX/XXX/blobs/uploads/XXX?_state=…: EOF

Can also be reproduced on 3.9 cluster

Version-Release number of selected component (if applicable):

OpenShift 3.7
OpenShift 3.9
ose-haproxy-router:v3.9.33


How reproducible:

Very reproducible

Steps to Reproduce:

1. Set router reload interval to 1s, the lowest allowed value. 

  oc -n default env dc/router RELOAD_INTERVAL=1s

2. Create project for tests:

  oc -n default new-project --skip-config-write test-project

3. Create route to trigger configuration change in router reload:

  oc -n test-project create route edge test --service test --port 80

4. Start patching route regularily:

  while sleep 1; do oc -n test-project patch -p '{"spec": {"to": {"weight": '"$((1 + (RANDOM % 250)))"'}}}' route/test; done

5. Observe "oc -n default logs -f dc/router". Router should reload once a second or thereabout.

6. Start cleanup job in case quotas and/or limitranges are active on project:

  while sleep 60s; do oc -n test-project delete istag --all; done

7. Start watching Docker logs on client (command for upstream-provided packages, may vary depending on test environment):

  sudo journalctl -f -u docker

8. Allow Docker daemon to push to registry.

  oc whoami -t | \
  sudo docker login -u "$(oc whoami)" --password-stdin registry.example.com

9. Write reproduction script

  $ cat >test-app.bash <<'EOF' && chmod +x test-app.bash
#!/bin/bash

set -e -u -o pipefail

rev="${1:?}"

tmpdir=$(mktemp -d)
trap 'date >&2; rm -rf "$tmpdir"' EXIT

tag="registry.example.com/test-project/test-app:${rev}"

cd "$tmpdir"

while true; do
  {
    echo "pid=$$"
    echo "random=$RANDOM"
    date
  } > data

  {
    echo 'FROM scratch'
    echo 'COPY ["data", "/"]'
  } > Dockerfile

  docker build -t "$tag" .
  date >&2
  docker push "$tag"
  date >&2
done

# vim: set sw=2 sts=2 et :
EOF

* Start reproduction script. I used 4 instances.

 ./test-ap.bash latest1
 ./test-app.bash latest2
  etc.


Actual results:

Eventually one or multiple reproduction scripts should fail with an error message, possibly one of those listed at the beginning.

Expected results:

Images are pushed correctly every time.

Additional info: