How to find out which ports are in use

To list all the ports in use on your machine, do:

netstat -anf inet

To see which process is using a specific port, do:

// sudo lsof -i :<portnumber>
sudo lsof -i :80

The above will list all processes using port 80. To kill a process, do:

// kill -9 <processid>
kill -9 51377