1、查看登录用户：
[root@TiaoBan- bin]# w
:: up days, :, users, load average: 1.90, 1.75, 1.84
USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT
eversec pts/ 102.112.11.113 : .00s .31s .01s sshd: eversec [priv]
eversec pts/ 102.112.11.113 : .00s .49s .01s sshd: eversec [priv]
eversec pts/ 102.112.11.113 : .00s .01s .01s sshd: eversec [priv]
2、通知用户：
echo -e '\033[31mI will close your connection!!!\033[0m' >/dev/pts/
3、关闭用户连接：
fuser -k /dev/pts/