shell script to shutdown/restart Linux system

Question

Is there any suitable shell script for shutting down or restarting a Linux machine? I have tried a shell script for shutdown, but when I enter sudo shutdown it will ask for the password. How we can enter the password using the script?

Answer 1

Another, in my opinion cleaner approach:

Create a new file in /etc/sudoers.d/ with content:

%users ALL=NOPASSWD: /sbin/shutdown
%users ALL=NOPASSWD: /sbin/reboot

This causes sudo to not ask for the password, if any user of group "users" tries to execute a shutdown or reboot. Of course you can also specify another group, maybe a newly created group for finer control of reboot permissions.

More information about the other possible settings for sudo can be found in the Manpage.

Answer 2

Yes, use the -S switch which reads the password from STDIN:

$echo <password> | sudo -S <command>

So to shut down the machine, your command would be like this (just replace <password> with your password):

$echo <password> | sudo -S poweroff

Exposing your password is generally bad idea search for something that can protect / hide it. In the past I've used Jenkins plugins to do this while executing the scripts regularly.