

I had the same problem: Debian host + official Jellyfin Docker image, all set up according to the official guide, but it would fail to transcode anything.
There was no relevant information about what was wrong in the logs so what I did was:
- Copy the ffmpeg command from the logs.
docker exec -itinto the Jellyfin container.- run the same ffmpeg command manually so I could see the error directly.
Long story short, because the Nvidia toolkit uses the driver/libraries from the host, the error was that I was missing the library libnvidia-encode1 on the host. After installing that, everything works as it should.



Briefly addressing the RAID types you mentioned:
Now, you mentioned not wanting ZFS due to complexity, but really, it is no more complex to manage than BTRFS. It’s fairly easy to get it working on any modern Linux distro (Ubuntu has support out-of-the-box, Debian has it packaged as a DKMS module, Arch has it in AUR, and so on).
With ZFS, you could create a RAID-Z1 (equivalent to a RAID-5) without any of the performance penalties or risks that BTRFS RAID-5 has. Both have pretty much them same features, with the main difference that ZFS can’t be “re-balanced” to a different disk layout like BTRFS can, but it will also generally not corrupt your data if you look at it wrong. Everything else maps pretty much 1:1 between them. Both support: