Let’s say that several users are connected through SSH.
First look at the list of online users:
w
Suppose the following information is displayed (where test is the user’s login):
USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT test tty1 11:20 1:07 0.03s 0.03s -bash test pts/0 192.168.1.5 11:21 13.00s 0.02s 0.02s -bash test pts/1 192.168.1.3 11:21 0.00s 0.02s 0.00s w
tty1 – it is a client logged in locally, that is, it is located near the computer.
pts/1 – judging for example on IP and WHAT, let’s assume that it’s us, accordingly pts/0 is the client of which we want to disconnect.
See the list of processes and their PID:
ps faux |grep sshd
At me it was displayed:
root 946 0.0 0.5 65508 5368 ? Ss 12:00 0:00 /usr/sbin/sshd -D root 1147 0.0 0.6 92828 6920 ? Ss 12:01 0:00 \_ sshd: test [priv] test 1178 0.0 0.3 92828 3384 ? S 12:01 0:00 | \_ sshd: test@pts/0 root 1192 0.0 0.6 92828 6592 ? Ss 12:02 0:00 \_ sshd: test [priv] test 1223 0.0 0.3 92828 3532 ? S 12:02 0:00 \_ sshd: test@pts/1 test 1248 0.0 0.0 15468 956 pts/1 S+ 12:25 0:00 \_ grep --color=auto sshd
We find test@pts/0 and accordingly 1178 is the required PID.
We terminate the process by specifying its ID, after which the user will immediately disconnect:
sudo kill -9 1178
See also my articles:
Configuring SSH session timeout
Installing and Configuring SSH