hi, if listing the reboot, I can see it is a soft link to halt. $ ls -l /sbin/reboot lrwxrwxrwx 1 root root 4 Oct 6 14:23 /sbin/reboot -> halt and halt can be executed by others, # ls -l /sbin/halt -rwxr-xr-x 1 root root 10208 Jan 5 2005 /sbin/halt however, when I tried to run the reboot command as a normal user, it says only root can do that, why?