Emby not updating library when requested

[lazynooblet 0]

When performing a POST request to emby server at /Library/Media/Updated, Emby is responding with HTTP 204, but on the Emby interface I don't get the new media until I manually choose "Scan Library Files", or wait for the scheduled scan.

The system is in front of Nginx as a reverse proxy, so I'm able to log the POST request and its contents, here is an example:

10.10.10.111 -  [08/May/2026:16:28:21 +0000] "POST /Library/Media/Updated HTTP/2.0" 204 883 "" "Radarr/6.1.1.10360 (alpine 3.23.4)" "{
  "updates": [
    {
      "path": "/storage/Media/Movies/The.Green.Mile.1999",
      "updateType": "Created"
    }
  ]
}"

Emby logs, in debug mode, at the time of the request show:

2026-05-08 16:28:21.500 Info LibraryService-0HNKV2FO5P1SM:00000001: http/1.1 POST http:/xxxx/Library/Media/Updated. Source Ip:10.10.10.11, UserAgent: Radarr/6.1.1.10360 (alpine 3.23.4)
2026-05-08 16:28:21.500 Info LibraryService-0HNKV2FO5P1SM:00000001: http/1.1 Response 204 to 10.10.10.11. Time: 0ms. POST http:/xxxx/Library/Media/Updated.

I can confirm that the path is correct, and exists:

# docker exec -it emby ls -lA /storage/Media/Movies/The.Green.Mile.1999
total 9830420
-rw-rw-r--    1 6000     6000     10066348683 Sep 23  2024 The.Green.Mile.1999.Bluray-1080p-Ralphy.mkv

The path "/storage/Media/Movies" matches that of the "Movies" library.

For the library settings, I have tried with and without the "Real-time monitoring" option enabled.
I've refreshed the page, closed browser, used incognito, used another device (AndroidTV) etc.
As soon as I hit "Scan Library Files", within a few seconds the movie will show in the library.

Emby 4.9.3.0 running in docker
docker-compose file:

Spoiler

services:
  emby:
    image: emby/embyserver
    container_name: emby
    environment:
      - UID=1000
      - GID=1000
      - GIDLIST=1000,44,992
    volumes:
      - /data/docker/volumes/emby/config:/config
      - /data/docker/volumes/emby/transcode:/transcode
      - /data/docker/volumes/emby/metadata:/metadata
      - /data/docker/volumes/emby/cache:/cache
      - media:/storage/Media
      - /etc/ssl/private:/etc/ssl/private:ro
    networks:
      - net
    devices:
      - /dev/dri:/dev/dri
    restart: unless-stopped

  nginx:
    image: nginx
    container_name: nginx
    volumes:
      - /data/docker/volumes/nginx/config:/etc/nginx
      - /etc/ssl/private:/etc/ssl/private:ro
    networks:
      - net
    ports:
      - 443:443
    restart: unless-stopped

networks:
  net:

volumes:
  media:
    driver: local
    driver_opts:
      type: nfs
      o: addr=10.10.10.240,ro,nolock
      device: ":/volume1/storage/Media"