This is a docker compose that I know works for qbittorrent behind gluetun.

I wonder if you are missing the “network_mode: service:gluetun” part?

qbittorrent: image: lscr.io/linuxserver/qbittorrent:latest container_name: qbittorrent2 network_mode: service:gluetun environment: - PUID=1000 - PGID=1000 - TZ=Etc/UTC - WEBUI_PORT=9090 - TORRENTING_PORT=6882 volumes: - /path/to/qbittorrent/appdata:/config - /mnt/JellyFinContent/Data/torrents:/data/torrents #optional

ports:

- 9090:9090

- 6882:6882

- 6882:6882/udp

depends_on:
  gluetun:
    condition: service_healthy
restart: unless-stopped

Gluetun and mullvad works for sure but, yes, you do need to modify some settings in the compose file. At least I did to get it work.