When to Shut Down a System
The following table lists system administration tasks and the type of shutdown that
is needed to initiate the task.
Table 8-1 Shutting Down a System
Reason for System Shutdown |
Appropriate Run Level |
For More
Information |
To turn off system power due to anticipated power outage |
Run level 0,
where it is safe to turn off power |
Chapter 10, Shutting Down a System (Tasks) |
To change kernel parameters in
the /etc/system file |
Run level 6 (reboot the system) |
Chapter 10, Shutting Down a System (Tasks) |
To perform file system maintenance,
such as backing up or restoring system data |
Run level S (single-user level) |
Chapter 10, Shutting Down a System (Tasks) |
To repair
a system configuration file such as /etc/system |
See When to Boot a System |
N/A |
To add or remove hardware
from the system |
Reconfiguration boot (also to turn off power when adding or removing
hardware) Reconfiguration boot (shut down and turn off power when adding or removing devices,
if the devices are not hot-pluggable) |
Adding a Peripheral Device to a System in System Administration Guide: Devices and File Systems |
To repair an important system file
that is causing system boot failure |
See When to Boot a System |
N/A |
To boot the kernel debugger (kmdb)
to track down a system problem |
Run level 0, if possible |
Chapter 10, Shutting Down a System (Tasks) |
To recover from a
hung system and force a crash dump |
See When to Boot a System |
N/A |
Reboot the system by using
the kernel debugger (kmdb), if the debugger can't be loaded at runtime. |
Run level
6 (reboot the system) |
For SPARC based systems: SPARC: How to Boot the System With the Kernel Debugger (kmdb) For x86 based systems: ,x86: How to Boot a System With the Kernel Debugger in the GRUB Boot Environment (kmdb) |
For examples of shutting down a server or a stand-alone system, see
Chapter 10, Shutting Down a System (Tasks).