Ubuntu View all login users and their process IDs

Ubuntu under the top can show how many users are currently landing, if you find that more than one user to determine whether there is an abnormal landing, you can use the WHO command to view all current landing users and their login time and IP address.

If you find that there is an abnormal landing, you can use the Who-a command to view the user's process number of an abnormal login, using root permission to use the kill-9 command force kill the process, the user will be forced to kick.

In addition, to see the logon user's process number, you can also use NETSTAT-ANP to view, because many times the connection to Ubuntu is SSH way, so see the connection on the 22-port process is who can, but this method shows a complex information, as a simple direct.