I am getting jupyterhub Spawn failed error while trying to login after I upgraded to latest jupyterhub 1.4.2 in our server.
Exception in Future <Task finished coro=<BaseHandler.spawn_single_user.<locals>.finish_user_spawn() done, defined at /opt/anaconda3/lib/python3.7/site-packages/jupyterhub/handlers/base.py:900> exception=TimeoutError("Server at http://127.0.0.1:36379/user/username/ didn't respond in 300 seconds")> after timeout