Error when modifying or uploading file from GUI - API is not accesible

I am updating Gitlab that I have installed on a server with Red Hat 8.1 Operating System. The version I’m starting is 13.0.14. In this version everything works correctly. The installation we do is a source installation (not omnibus). In this installation we configure a relative URL and the server is behind an nginx balancer.

The reported problem is the following:

The process documented on the official Gitlab page is followed to update to Gitlab version 13.1.11 from 13.0.14. The update process is successful. At the end of the update process, the system check is launched, giving everything OK.


The GUI is accessed, and some basic tests are carried out. These tests are to modify, add or delete any file in any project that we have as a test, giving the error “API is not accessible” as seen in the attached screenshot.


When I saw this error, what I changed to verify where the problem lies was to remove the relative URL and only access it by the machine name. Doing the same tests, the same error appears.

At the same time, I installed one of the latest versions of Gitlab, version 15.11.13, on another machine with RH8. It was installed correctly and the same tests were done with different configuration changes:

  • Configuration - Factory and access by machine name - Tests OK
  • Configuration - With LDAP and access by machine name - Tests OK
  • Configuration - With LDAP, with access by machine name and relative URL (/gitlab) - Tests not OK - Error denied by custom hooks

The relative URL configuration is removed, and the tests performed work correctly.

In the different logs I don’t see anything related to these two errors, API is not accessible and Error denied by custom hooks.

Any suggestion?