Problem reconnecting to jupyter notebook

[matssk]

Applies To

• Notebooks (.ipynb files)
• Interactive Window and/or Cell Scripts (.py files with #%% markers)

What happened?

If the jupyter notebook server restarts, the plugin refuses to reconnect until I restart Visual Studio Code. It says "Unable to connect to the remote server. Ensure the server is running and reachable." This error message will persist until Visual Studio Code is restarted, even though the jupyter server is already back up.

VS Code Version

1.96

Jupyter Extension Version

2024.11.0

Jupyter logs

Coding Language and Runtime Version

No response

Language Extension Version (if applicable)

No response

Anaconda Version (if applicable)

No response

Running Jupyter locally or remotely?

Remote

[DonJayamanne]

Please could you enable logging as follows:

• Open settings & go into Jupyter->Logging
• Change the value to trace
• Reload VS Code,
• Attempt to repro the issue & then copy the output from the Jupyter output panel (use the command Jupyter: Show Output to get to the logs).

[matssk]

I won't be able to do that for a few weeks, but I was looking a bit at server logs and it looks like maybe what's happening is it tries logging in again with the same cookies/headers, but these are not valid any more since the server restarted, so it should retry with the token and it seems maybe it's not doing that unless vscode is restarted.

[DonJayamanne]

Do you have a notebook connected to a kennel?
If you do, and then restart the Jupiter server then the kernel that was connected to the notebook is now lost and reconnecting doesn't work.

Hence you need to reselect a kennel spec to get around this.

Is this what you are running into.

[matssk]

Yes. After restarting the jupyter server I click "Select kernel", then "Existing Jupyter server" and I choose the server there. When I try to reselect the kernel and press the reload icon, it does not connect. After I restart vscode I can try reconnecting to the kernel and it works, but I have to enter the token again.

[DonJayamanne]

and it works, but I have to enter the token again.

Oh so you enter a while new token, is that correct?
And the request is to be provided to enter the new token instead of having to restart vscode.

[matssk]

I don't get a request for a new token unless I restart vscode, it just says it can't connect.