I have a Python script that creates docker run commands and executes them. This runs just fine from my /home/myuser directory, but if I move it to /opt/myuser (having to sudo run everything there), all of a sudden my docker run command can't find the mounted data. Specifically, my docker run string is docker run --gpus all --privileged -v /home/myuser/data/input:/input/ -v /home/myuser/data/output:/output/ -v /home/myuser/data/key:/key mydocker process /input/filename -k /key/mykey.key -o /output/ And the Docker error output says: "error": "a given key file \"/key/mykey.key\" does not exist" Any idea why moving this script to /opt/ all of a sudden fails when it's producing the same exact command that successfully completes when in my /home/ directory? I'm executing this from the Python script with: subprocess.call(docker_run_string, shell=True, stderr=log) May the subprocess.call() be the culprit? Continue reading...