The symptoms are that hte page is not secure:
And there is a warning in the log in box
This can happen if you do not use the https:// segment at the begining of the notebook server URL. Please add it to the URL and you will get to the secure site.
I get an error “Kernel restarting. The kernel appears to have died. It will restart automatically.”
This can occur if your notebook server is running out of memory. It could have several causes:
you have too many opened notebooks. You can stop the notebooks you do not need in the home screen, on the “Running” tab by clicking on the “shutdown” button for the notebooks you are not currently needing.
your code needs more memory than has been allocated. The notebooks normally have enough memory to perform the task you are asked to complete.
Yes, after 1-2 hours of inactivity sessions are automatically closed to save resources. Since notebooks are automatically saved there should not be any data loss but you will need to re-execute the notebook to restore the state of the python session.
Depending on how busy the notebook server is starting a notebook can feel quite long. It is normal and not a cause for concern.