Operating system

Ubuntu 18.04.4 LTS

`nbgrader --version`

Python version 3.7.7 (default, Mar 26 2020, 15:48:22) [GCC 7.3.0] nbgrader version 0.6.1

`jupyterhub --version` (if used with JupyterHub)

1.0.0 ERROR:asyncio:Task exception was never retrieved future: <Task finished coro=<JupyterHub.launch_instance_async() done, defined at /opt/tljh/user/lib/python3.7/site-packages/jupyterhub/app.py:2477> exception=SystemExit(0)> Traceback (most recent call last): File "/opt/tljh/user/lib/python3.7/site-packages/jupyterhub/app.py", line 2492, in launch_instance loop.start() File "/opt/tljh/user/lib/python3.7/site-packages/tornado/platform/asyncio.py", line 149, in start self.asyncio_loop.run_forever() File "/opt/tljh/user/lib/python3.7/asyncio/base_events.py", line 541, in run_forever self._run_once() File "/opt/tljh/user/lib/python3.7/asyncio/base_events.py", line 1786, in _run_once handle._run() File "/opt/tljh/user/lib/python3.7/asyncio/events.py", line 88, in _run self._context.run(self._callback, self._args) File "/opt/tljh/user/lib/python3.7/site-packages/jupyterhub/app.py", line 2479, in launch_instance_async await self.initialize(argv) File "/opt/tljh/user/lib/python3.7/site-packages/jupyterhub/app.py", line 2085, in initialize super().initialize(args, kwargs) File "", line 2, in initialize File "/opt/tljh/user/lib/python3.7/site-packages/traitlets/config/application.py", line 87, in catch_config_error return method(app, *args, *kwargs) File "/opt/tljh/user/lib/python3.7/site-packages/traitlets/config/application.py", line 297, in initialize self.parse_command_line(argv) File "", line 2, in parse_command_line File "/opt/tljh/user/lib/python3.7/site-packages/traitlets/config/application.py", line 87, in catch_config_error return method(app, args, kwargs) File "/opt/tljh/user/lib/python3.7/site-packages/traitlets/config/application.py", line 532, in parse_command_line self.exit(0) File "/opt/tljh/user/lib/python3.7/site-packages/traitlets/config/application.py", line 654, in exit sys.exit(exit_status) SystemExit: 0

`jupyter notebook --version`

6.0.3

Expected behavior

see Actual behavior

Actual behavior

Our machine has two network interfaces. When I go from the local side (http://10.x.x.x) on 'Courses' everything is working fine, but when I got from the WAN side (http://193.x.x.x) on 'Courses' I get the error message: Traceback (most recent call last): File "/opt/tljh/user/lib/python3.7/site-packages/nbgrader/server_extensions/course_list/handlers.py", line 172, in get local_courses = yield self.check_for_local_formgrader(config) File "/opt/tljh/user/lib/python3.7/site-packages/tornado/gen.py", line 735, in run value = future.result() File "/opt/tljh/user/lib/python3.7/site-packages/tornado/gen.py", line 742, in run yielded = self.gen.throw(*exc_info) # type: ignore File "/opt/tljh/user/lib/python3.7/site-packages/nbgrader/server_extensions/course_list/handlers.py", line 63, in check_for_local_formgrader response = yield http_client.fetch(url, headers=header) File "/opt/tljh/user/lib/python3.7/site-packages/tornado/gen.py", line 735, in run value = future.result() ConnectionRefusedError: [Errno 111] Connection refused

cat /etc/jupyterhub/jupyterhub_config.py | egrep -v "(^#.*|^$)" c.JupyterHub.ip = '0.0.0.0' c.JupyterHub.port = 80

Do I have to configure something more?

Steps to reproduce the behavior

see Actual behavior

Kind regards, K1LLUM1N471

Hi,

Same issue, I don't manage to access courses from JupyterHub Web UI (TLJH installed).