Docker run cannot find existing file?

Question

I am trying to run this command to test if the gpu is being recognized

docker run --rm --device /dev/dri:/dev/dri jrottenberg/ffmpeg:5.1.2-vaapi2004 -hwaccel vaapi -hwaccel_output_format vaapi -i /root/Server_transcoder/bbb_sunflower_1080p_30fps_normalORIG.mp4 -c:v h264_vaapi /tmp/example.mp4

And it errors out with: /root/Server_transcoder/bbb_sunflower_1080p_30fps_normalORIG.mp4: No such file or directory

The file exists in there and the path is not misspelled - I checked like 10 times

What could be the problem here?? I am clueless

Answer 1

the docker run command was missing a mounting option - and the file did not need an absolute path, just a relative one to the mounting folder

this command worked:

docker run --rm --device /dev/dri:/dev/dri -v /root/Server_transcoder:/tmp/workdir  jrottenberg/ffmpeg:5.1.2-vaapi2004 -hwaccel vaapi -hwaccel_output_format vaapi -i bbb_sunflower_1080p_30fps_normalORIG.mp4 -c:v h264_vaapi /tmp/example.mp4