Type who
the -u
flag; the PID is the number off to the right:
> who -u ec2-user pts/1 2019-11-14 16:52 00:02 16035 (104.245.199.125)
Look up the process ID of the shell their TTY is connected to:> ps t PID TTY STAT TIME COMMAND
16035pts/1
Ss 0:00 zsh
Laugh at their impending disconnection (this step is optional, but encouraged)> echo "HAHAHAHAHAHAHAHA" | write
ec2-userpts/1
Kill the corresponding process:
> kill -9
16035