There are several ways to shut down Linux, most of which act immediately. Sometimes you want to schedule shutdown for a particular time and notify other remote users beforehand so they can prepare. To delay shutdown and notify other remote users, run:

shutdown -h +เวลา “ข้อความแจ้งเตือน”

For example, to shut down in one minute and notify other remote users with “Server is going down for maintenance”, run:

root@om:~# shutdown -h +1 "Server is going down for maintenance"

Output

Broadcast message from tum@ezylinux
        (/dev/pts/0) at 12:12 ...

The system is going down for halt in 1 minute!
Server is going down for maintenance