Runlevel Utilities; Shutting Down - Red Hat ENTREPRISE LINUX 5 Installation Manual

Chapter 33. Boot Process, Init, and Shutdown
For more information on single-user and rescue mode, refer to the chapter titled Basic
System Recovery in the Red Hat Enterprise Linux Deployment Guide.
It is possible to change the default runlevel at boot time by modifying the arguments passed by the
boot loader to the kernel. For information on changing the runlevel at boot time, refer to
"Changing Runlevels at Boot

33.4.2. Runlevel Utilities

One of the best ways to configure runlevels is to use an initscript utility. These tools are designed
to simplify the task of maintaining files in the SysV init directory hierarchy and relieves system
administrators from having to directly manipulate the numerous symbolic links in the subdirectories of
/etc/rc.d/.
Red Hat Enterprise Linux provides three such utilities:
• /sbin/chkconfig — The /sbin/chkconfig utility is a simple command line tool for maintaining
the /etc/rc.d/init.d/ directory hierarchy.
• /usr/sbin/ntsysv — The ncurses-based /sbin/ntsysv utility provides an interactive text-based
interface, which some find easier to use than chkconfig.
• Services Configuration Tool — The graphical Services Configuration Tool (system-config-
services) program is a flexible utility for configuring runlevels.
Refer to the chapter titled Controlling Access to Services in the Red Hat Enterprise Linux Deployment
Guide for more information regarding these tools.

33.5. 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
and
/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 the Red Hat Enterprise
Linux Deployment Guide.
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.
360
Time".
Section 9.8,