You need to use the sudo command to grant a permission to other users to shutdown your server. The sudo command allows a permitted user to execute a command as the superuser or another user, as specified in the /etc/sudoers file. Login as a root user and type the visudo command to edit the sudoers file.
You may wonder – why should I shutdown the Linux box box automatically? It depends upon your situation. For example, your downloading couple of tar balls and you want to go home. You can schedule a job to shutdown Linux after downloading is completed. Linux/UNIX/BSD/OS X comes with at and cron commands to automate task. Almost all common task can be automated using at command.
It is true that Gnome desktop provides nice facility to logoff, shutdown or restart computer with dialog. You can create a nice shortcut to avoid the GUI confirmation dialog box to speed up work. (A) Shutdown computer i) Right click on Desktop > Select Create Launcher ii) Type the Command in text box “sudo /sbin/shutdown [...]