Booting

The Solaris 2.6 boot process makes system administration easier. Some of the major changes include:

• The kernel is self-configuring so you no longer need to rebuild it manually.

• Kernel memory consumption is reduced by automatic loading of devices when first opened.

• File systems are checked only when necessary, improving boot time.

• The boot block can read UNIX file systems, eliminating boot errors when the boot program moves.

• Third-party bootable devices are supported.

• Secondary boot programs, ufsboot and inetboot, have been modified to read CacheFS file systems. This new booting capability enables Solstice AutoClient(TM) systems to boot more quickly and with less impact on network resources.

• The SunOS release 4.x fastboot command is available only on Solaris 2.6 systems that have the SunOS/BSD Source Compatibility Package installed. The fastboot command is obsolete in Solaris 2.6 systems because file systems are only checked if the file system state is identified as not clean.

• The SunOS release 4.x halt and reboot commands have shutdown(1M) and init(1M) equivalents in the SunOS release 5.6 software.

In the Solaris 2.6 operating environment, the shutdown and init commands are the preferred way to halt, shut down, or reboot your system. While the reboot command is available in the Solaris 2.6 operating environment, it brings the system down quickly without shutting down services in an orderly way. Table 8-1 shows the SunOS release 5.6 commands that replace SunOS release 4.x commands.

Table 8-1 SunOS release 5.6 Replacements for reboot and fastboot

SunOS release 4.x Command	SunOS release 5.6 Command Replacement
reboot	shutdown -i -6, init 6
fastboot	boot, init 6

boot Command Changes

The SunOS release 5.6 software has these additional options for the boot command:

• Type boot -r when you add new hardware or alter its location. This option creates the physical and logical device names, with the logical device name linked to the physical device name.

• Type boot -v when you want to see all the system bootup messages; the default is to boot silently. The messages are always stored in the /var/adm/messages file.

• Type boot -a when you want to be prompted for the name of an alternate kernel, /etc/system file, or path name for kernel module directories.

Booting From the PROM

Be aware of these changes when booting from PROM:

• The PROM loads bootblk from the disk. This file is similar to the previous SunOS release 4.x boot block except that it is specific to the UFS file system.

  As in the SunOS release 4.x software, you need to use installboot(1M) to install boot blocks on a partition to be used for booting.

• bootblk opens the boot device and, using the file system you specify, finds and loads ufsboot.

• The boot PROM loads the kernel, /kernel/genunix, after ufsboot is loaded into memory. SunOS release 4.x systems used /vmunix; however, in the SunOS release 5.6 software the /kernel directory contains all platform-independent kernel modules, including unix, needed to boot the system.

• The kernel, in turn, loads other drivers, such as esp, from the /kernel/drv directory. These drivers had to be built as part of the SunOS release 4.x kernel but can be dynamically loaded in SunOS release 5.6 systems when they are needed.

• The /sbin/init command generates processes to set up the system based on the directions in /etc/inittab. The next section describes the run levels that init uses.

Summary of Boot Differences

Table 8-2 summarizes booting differences.

Table 8-2 Summary of Booting Differences

SunOS release 4.x	SunOS release 5.6	Feature
bootsd	bootblk	Now loads ufsboot from disk
boot program	ufsboot	Now loads unix from disk
/vmunix	/kernel/genunix	Bootable kernel image
boot.sun4c.sunos.4.1	inetboot	Mounts and copies unix from network
rc.boot rc.single	/etc/rcS	Mounts /usr and checks file systems
rc.local	/etc/rc2 /etc/rc3	System config scripts
/etc/config	modload /etc/system	Customizes system kernel, loads modules as needed
Prom monitor, single user, multiuser	Run states 0 - 6, and S	System run levels
/dev/sd1g	/dev/dsk/c0t1d0s6	More descriptive logical device names. See "Device Naming Conventions".
MAKEDEV	boot -r, add_drv	Makes device nodes