1.5. Shutting Down

To shut down Red Hat Enterprise Linux, the root user may issue the /sbin/shutdown command. The shutdown man page has a complete list of options, but the two most common uses are:
/sbin/shutdown -h now
/sbin/shutdown -r now
After shutting everything down, the -h option halts the machine, and the -r option reboots.
PAM console users can use the reboot and halt commands to shut down the system while in runlevels 1 through 5. For more information about PAM console users, refer to Section 16.7, “PAM and Device Ownership”.
If the computer does not power itself down, be careful not to turn off the computer until a message appears indicating that the system is halted.
Failure to wait for this message can mean that not all the hard drive partitions are unmounted, which can lead to file system corruption.