Guidelines for Booting a System

Bootstrapping is the process of loading and executing the bootable operating system. Typically, the stand-alone program is the operating system kernel, but any stand-alone program can be booted. After the kernel is loaded, it starts the UNIX system, mounts the necessary file systems, and runs /usr/sbin/init to bring the system to the initdefault state that is specified in the /etc/inittab file.

Keep the following guidelines in mind when booting a system:

After a SPARC based machine system is shut down, it is booted by using the boot command at the PROM level. After a SPARC based system is turned on, the system firmware (in PROM) executes a power-on self-test (POST). The form and scope of these tests depends on the version of firmware in your system. After the tests have successfully completed, the firmware attempts to auto boot, if the appropriate flag has been set in the non-volatile storage area that is used by the firmware. The name of the file to load, and the device to load it from, can also be manipulated.
An x86 based system is booted by selecting an operating system in the GRUB menu that is displayed at boot time. If no operating system is selected, the system boots the default operating system that is specified in the grub.cfg file.
A system can also be rebooted by turning the power off and then back on.

Reasons to Boot a System

The following table lists reasons that you might need to boot a system. The system administration tasks and the corresponding boot option that is used to complete the task is also described.

Table 1-1 Booting a System

Reason for System Reboot	Appropriate Boot Option	For More Information
Turn off system power due to anticipated power outage.	Turn system power back on	Chapter 3, Shutting Down a System (Tasks)
Change kernel parameters in the `/etc/system` file.	Reboot the system to a multiuser state (run level 3 with NFS resources shared)	How to Boot a System to a Multiuser State (Run Level 3)
Perform file system maintenance, such as backing up or restoring system data.	Press Control-D from a single-user state (run level S) to bring the system back to a multiuser state (run level 3)	How to Boot a System to a Single-User State (Run Level S)
Repair a system configuration file such as `/etc/system`.	Interactive boot	How to Boot a System Interactively
Add or remove hardware from the system.	Reconfiguration boot (turn on system power after adding or removing devices, if devices are not hot-pluggable)	Setting Up Disks for ZFS File Systems (Task Map) in Oracle Solaris 11.1 Administration: Devices and File Systems
Boot a system for recovery purposes due to a lost `root` password, or to fix a file system or a similar problem.	Depending on the error condition or problem, you might need to boot the system from media, mount the boot environment, or both.	Shutting Down and Booting a System for Recovery Purposes
x86 only: Recover from a problem with the GRUB configuration.	Recovery boot from media.	x86: How to Boot From Media to Resolve a Problem With the GRUB Configuration That Prevents the System From Booting
Recover from a hung system by forcing a crash dump.	Recovery boot	SPARC: How to Force a Crash Dump and Reboot of the System x86: How to Force a Crash Dump and Reboot of the System
Boot the system by using the kernel debugger (`kmdb`) to track down a system problem.	Booting `kmdb`	SPARC: How to Boot a System With the Kernel Debugger (`kmdb`) Enabled x86: How to Boot a System With the Kernel Debugger (`kmdb`) Enabled

Skip Navigation Links
Exit Print View
	Booting and Shutting Down Oracle Solaris 11.1 Systems Oracle Solaris 11.1 Information Library