500 error when uploading a file in GitLab instance on OpenShift Cluster

Summary

When trying to upload a file to GitLab application, request fails with 500 error.

Steps to reproduce

  1. Create OpenShift cluster following "OpenShift Cluster Setup" guide
  2. Install GitLab operator on the cluster
  3. Try to upload a file

Logs

webservice {"method":"GET","path":"/gitlab-instance-df04072d/Monitoring/-/issues/1/realtime_changes","format":"json","controller":"Projects::IssuesController","action":"realtime_changes","status":200,"time":"2021-04-13T17:47:38.516Z","params":[{"key":"na │
│ webservice *** /var/log/gitlab/production.log ***                                                                                                                                                                                                              │
│ webservice Started POST "/gitlab-instance-df04072d/Monitoring/uploads/authorize" for 176.52.99.36 at 2021-04-13 17:47:41 +0000                                                                                                                                 │
│ webservice Processing by Projects::UploadsController#authorize as JSON                                                                                                                                                                                         │
│ webservice   Parameters: {"namespace_id"=>"gitlab-instance-df04072d", "project_id"=>"Monitoring"}                                                                                                                                                              │
│ webservice Completed 500 Internal Server Error in 123ms (ActiveRecord: 3.0ms | Elasticsearch: 0.0ms | Allocations: 25677)                                                                                                                                      │
│ webservice                                                                                                                                                                                                                                                     │
│ webservice Excon::Error::Socket (getaddrinfo: Name or service not known (SocketError)):                                                                                                                                                                        │
│ webservice                                                                                                                                                                                                                                                     │
│ webservice lib/object_storage/direct_upload.rb:216:in `block in upload_id'                                                                                                                                                                                     │
│ webservice lib/gitlab/utils/strong_memoize.rb:30:in `strong_memoize'                                                                                                                                                                                           │
│ webservice lib/object_storage/direct_upload.rb:215:in `upload_id'            
Context

The issue was found when investigating GitLab QA failures in https://gitlab.com/gitlab-org/gl-openshift/gitlab-operator/-/merge_requests/114#note_546074134