Database connection working in test frontend, but not deployment

[dr-who123]

I have been trying to install Nominatim 4.5 on my Fedora server for several days and finally got to the point where everything seems to be correctly installed, but on http://localhost/status I get "ERROR: Database connection failed"

However, when testing the frontend with "nominatim serve" the status reports "OK" and I can run test queries. It seems the database has correctly been established, but the frontend just cannot connect to it.
How can I solve this problem?

Edit: While trying to solve the problem, I now get ERROR 500 Internal Server Error.
The logs look normal:

[2024-10-08 11:33:58 +0200] [1063] [INFO] Starting gunicorn 23.0.0 [2024-10-08 11:33:58 +0200] [1063] [INFO] Listening at: unix:/run/nominatim.sock (1063) [2024-10-08 11:33:58 +0200] [1063] [INFO] Using worker: uvicorn.workers.UvicornWorker [2024-10-08 11:33:58 +0200] [1303] [INFO] Booting worker with pid: 1303 [2024-10-08 11:33:58 +0200] [1306] [INFO] Booting worker with pid: 1306 [2024-10-08 11:33:58 +0200] [1307] [INFO] Booting worker with pid: 1307 [2024-10-08 11:33:58 +0200] [1310] [INFO] Booting worker with pid: 1310 [2024-10-08 11:33:58 +0200] [1307] [WARNING] ASGI app factory detected. Using it, but please consider setting the --factory flag explicitly. [2024-10-08 11:33:58 +0200] [1306] [WARNING] ASGI app factory detected. Using it, but please consider setting the --factory flag explicitly. [2024-10-08 11:33:58 +0200] [1310] [WARNING] ASGI app factory detected. Using it, but please consider setting the --factory flag explicitly. [2024-10-08 11:33:58 +0200] [1303] [WARNING] ASGI app factory detected. Using it, but please consider setting the --factory flag explicitly. [2024-10-08 11:33:58 +0200] [1310] [INFO] Started server process [1310] [2024-10-08 11:33:58 +0200] [1307] [INFO] Started server process [1307] [2024-10-08 11:33:58 +0200] [1306] [INFO] Started server process [1306] [2024-10-08 11:33:58 +0200] [1303] [INFO] Started server process [1303] [2024-10-08 11:33:58 +0200] [1310] [INFO] Waiting for application startup. [2024-10-08 11:33:58 +0200] [1307] [INFO] Waiting for application startup. [2024-10-08 11:33:58 +0200] [1306] [INFO] Waiting for application startup. [2024-10-08 11:33:58 +0200] [1303] [INFO] Waiting for application startup. [2024-10-08 11:33:58 +0200] [1310] [INFO] Application startup complete. [2024-10-08 11:33:58 +0200] [1306] [INFO] Application startup complete. [2024-10-08 11:33:58 +0200] [1307] [INFO] Application startup complete. [2024-10-08 11:33:58 +0200] [1303] [INFO] Application startup complete.

systemctl status nominatim.service nominatim.socker and nginx are all active

[mtmail]

Are you using systemd to start the application server? Can you post your systemd configuration? https://nominatim.org/release-docs/4.5/admin/Deployment-Python/

The WorkingDirectory is important, Nominatim looks for a .env file in there.

The User needs to have database read permissions. There's an example at https://nominatim.org/release-docs/4.5/admin/Install-on-Ubuntu-24/#setting-up-postgresql sudo -u postgres createuser www-data