I have pulled the jupyter/datascience-notebook:latest image from docker hub and launched an instance container of it. I logged into the container through bash. Now i want to restart the server itself because i have made some modifications to a config file and need it to be picked up by the server; i am configuring nbgrader by the way.

I have found a command in a stackoverflow answer, to restart the server: it says sudo initctl restart jupyter-server --no-wait. Now when i type that command it asks me for a password for the user *jovyan” which i don’t know.
So how to come around it ?