System Administration Guide, Volume I

When to Shut Down a System

Table 5-2 provides a list of system administration tasks and the type of shut down needed to initiate the task.

Table 5-2 Shutting Down a System

If You Are ...  

Change to This Run Level ... 

See ... 

Turning off system power due to anticipated power outage 

Run level 0, where it is safe to turn off power 

Chapter 7, Shutting Down a System (Tasks)

Changing kernel parameters in the /etc/system file

Run level 6 (reboot the system) 

Chapter 7, Shutting Down a System (Tasks)

Performing file system maintenance, such as backing up or restoring system data 

Run level S (single-user mode) 

Chapter 7, Shutting Down a System (Tasks)

Repairing a system configuration file such as /etc/system

See "When to Boot a System"

N/A 

Changing pseudo device parameters in the /etc/system file

Reconfiguration boot 

"Tuning Kernel Parameters (Tasks)" in System Administration Guide, Volume II

Adding or removing hardware from the system 

Reconfiguration boot (plus turning off power when adding or removing hardware) 

"SPARC: How to Connect a Secondary Disk and Boot"

Repairing an important system file which is causing system boot failure 

See "When to Boot a System"

N/A 

Booting the kernel debugger (kadb) to track down a system problem

Run level 0, if possible 

Chapter 7, Shutting Down a System (Tasks)

Recovering from a hung system and you want to force a crash dump 

See "When to Boot a System"

N/A 

See Chapter 7, Shutting Down a System (Tasks) for examples of shutting down a server or standalone system.