Fix: Jupyter Notebook: The port 8888 is already in use, trying another port.

If you start a new session of Jupyter Notebook via the Terminal and you see something like "port 8888 is already in use", then a new port would be selected (usually 8889) you should be able to use your Notebooks on the web browser.

[I 06:07:28.137 NotebookApp] The port 8888 is already in use, trying another port.
[I 06:07:28.138 NotebookApp] Serving notebooks from local directory: /Users/c2ctechtv/Desktop/myproj2
[I 06:07:28.138 NotebookApp] Jupyter Notebook 6.5.4 is running at:
[I 06:07:28.138 NotebookApp] http://localhost:8889/?token=54e40f447444e0df392e94d5c6e2f389b6a756071a6e0300
[I 06:07:28.138 NotebookApp]  or http://127.0.0.1:8889/?token=54e40f447444e0df392e94d5c6e2f389b6a756071a6e0300
[I 06:07:28.138 NotebookApp] Use Control-C to stop this server and shut down all kernels (twice to skip confirmation).

If you want to know what's running at port 8888, you can run the below command in the Terminal.

% jupyter notebook list

Currently running servers:
http://localhost:8889/?token=54e40f44744...6a756071a6e0300 :: /Users/c2ctech/Desktop/myproj2
http://localhost:8888/?token=a777de...1343206cb92337b48d06 :: /Users/c2ctech/Desktop/myproj2)

As you can see, I have a Jupyter Notebook running on Port 8888

If you want to kill the session running on port 8888, do the following,

% lsof -t -i :8888
705
12538

Identify the PID for the port 8888 and run the kill -9 command.

% kill -9 12538