"Gitlab BlockedUrlError - URL is blocked: Requests to the local network are not allowed" - Unable to fix issue via Outbound requests

Problem to solve

I’m encountering an issue in GitLab where any attempt to make significant changes, such as deleting a project or adjusting repository permissions, results in a:

500 - We're sorry. Something went wrong on our end - Error

Upon further investigation, I discovered that the underlying error is the following:

HTTP_V2::BlockedUrlError - URL is blocked: Requests to the local network are not allowed

Troubleshooting

After researching the issue, I learned that enabling the 'Allow requests to the local network from web hooks and services’ option in the ‘Outbound requests’ settings should resolve the problem.

However, when I attempt to enable this setting in the GitLab UI, I encounter the same ‘500’ error, creating a chicken-egg problem.

Configuration

  • NGINX Proxy Manager that acts as a reverse proxy (docker container) for the Gitlab container
  • Gitlab 17.1.1-ee Docker Container instance

GITLAB_OMNIBUS_CONFIG: |
external_url ‘http:url.com’
nginx[‘listen_https’] = false
nginx[‘real_ip_header’] = ‘X-Forwarded-For’
nginx[‘real_ip_recusrive’] = ‘on’

  • Both in the same docker bridge network named “npm”

Versions

  • Self-managed, Gitlab ee version 17.1.1 ee, Docker Container

I’ve spent so much time on this issue, I really do not know what to do.
Any help is highly appreciated. Thank you very much.

Hey guys, I’ve just opened a +150 points bounty on Stackoverflow: "Gitlab BlockedUrlError - URL is blocked: Requests to the local network are not allowed" - Unable to fix issue via Outbound requests - Stack Overflow

Any hint is highly appreciated!