"upstream prematurely closed connection while reading response header from upstream" I'm using nginx and uwsgi stack.
However, other files worked just fine, just that particular file. So I decided to ignore the content of the error message which seemed to indicate some sort of configuration issue, and did the usual troubleshooting things like restarted the teacher's machine and tried to upload using other machines. We even tried changing the name of the file. Same exact error in the log whenever we tried to upload the file. From the front-end, what we saw is that the progress bar went to 100% and just as it was about to report that it had been successfully uploaded, I instead got a generic error message.
Then I simply used HandBrake to transcode it to another "format", worked the first time no problems.
Is there something potententially in the file that would cause the connection to prematurely close? Wrong headers, something like this? I have a feeling I'm completely ignorant about something kinda important here.