Trying to open any notebook/lab v5-7 makes terminal completely unresponsive

I opened an issue on GitHub: Trying to open any notebook/lab v5-7 makes terminal completely unresponsive · Issue #7429 · jupyter/notebook · GitHub . The debug messages and all the config settings are there. I’m pasting the description:

I run Jupyter on a supermicro CentOS 8 machine. I create an ssh tunnel and work on the machine from my browser. I had a running v6 installed through conda, but after a powerout, my notebooks would not open. Since then, I have installed several different version of notebook from 5 to 7 with the correct listed dependency versions (as far as I can tell) through both pypi and conda. I uninstalled and reinstalled every major release of python from 3.5 for the kernel trying to get it to work, but to no avail. I installed a python 2 kernel, and the same behavior persists. Soon as I try to create a new notebook or open a new one, the terminal on the HPC hangs and becomes unresponsive to everything including ctrl C.

This problem is machine specific. All triggered by a powerout and reboot. My best guess is that it’s a network file system issue. I can’t figure out how to fix this.