How Do You Terminate a Process Listening on a Given TCP Port?

Problem scenario
There is a process listening on a TCP port on your Linux system. How do you end it?

Solution
Assuming you want to terminate the process 5555, this is how you would find the PID:

sudo lsof -i :5555

To kill the process, the output of the above command will show you a PID. Run this command where 111222333 is the PID number you found above:

sudo kill -9 111222333