SOLVED: HW Transcoding issues and issue mapping /dev/dri to container

SOLVED: HW Transcoding issues and issue mapping /dev/dri to container - Printable Version

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+--- Thread: SOLVED: HW Transcoding issues and issue mapping /dev/dri to container (/t-solved-hw-transcoding-issues-and-issue-mapping-dev-dri-to-container)

HW Transcoding issues and issue mapping /dev/dri to container - TheChow - 2025-09-29

Edit: I forgot to mention I had Docker Desktop installed, and after some searching various places I found someone who had similar issues to mine and a reply saying they thought Docker Desktop may be an issue as they were unsure if it passes through devices. So I stripped Docker Desktop from my system and it works fine even without "privileged:true", but I need the user mapping.

I'm running KDE Neon 6.4.5 (Ubuntu 24.04LTS) on a AMD Ryzen 9 7940HS (Radeon 780M graphics) laptop. The system is up to date from apt-get and Discover.

I'm running into issues mapping /dev/dri to the Jellyfin container and have hit a wall in troubleshooting. I'm using the LinuxServer.io latest Jellyfin image.

Here's a trimmed version of my Docker compose.yaml

Code:
services:

  jellyfin:

    image: lscr.io/linuxserver/jellyfin:latest 

    privileged: true

    container_name: jellyfin

    group_add:

      - video

      - 992 # group id for render

    environment:

      - PUID=1000 # my uid and gid

      - PGID=1000

      - TZ=America/New_York

      - JELLYFIN_PublishedServerUrl=http://192.168.50.9 #optional

    devices:

      - /dev/dri:/dev/dri

    volumes:

      - /home/myusername/docker/jellyfin/config:/config

      - /home/myusername/docker/jellyfin/cache:/cache

      - /media/Movies:/data/Movies # several more mappings

    ports:

      - 8096:8096

      - 8920:8920 #optional

      - 7359:7359/udp #optional

      - 1900:1900/udp #optional

    restart: unless-stopped

If I don't have "privledge: true" I get an error "Error response from daemon: error gathering device information while adding custom device "/dev/dri": no such file or directory"

With privledge it launches with "docker compose up", but if I open a shell on the container I don't see /dev/dri; and attempting to use VAAPI HW transcoding fails. I've tried with and without my ID specified, both result in missing /dev/dri inside the container.

If I run "sudo docker compose up", and in the container I can see /dev/dri, and using the same settings in Jellyfin transcoding is successful.