SPARC The Boot PROM

Each system has a PROM (programmable read-only memory) chip with a program called the monitor. The monitor controls the operation of the system before the kernel is available. When a system is turned on, the monitor runs a quick self-test procedure that checks things such as the hardware and memory on the system. If no errors are found, the system begins the automatic boot process.

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SPARC - Some older systems may require PROM upgrades before they will work with the SunOS system software. Contact your local service provider for more information.

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SPARC The PROM Prompt

When the system is halted, the PROM monitor prompt is displayed and the type of prompt depends on your system type. Older Sun systems like the Sun4/nnn series, use the greater than sign (>) as the PROM prompt. Newer Sun systems use ok as the PROM prompt but support the > prompt.

* To switch from the > prompt to the ok prompt on newer Sun systems type the following command:

> n ok

SPARC How to Find the PROM Release for a System

* Type banner from the ok PROM prompt and press Return. Hardware configuration information, including the release number of the PROM, is displayed.

ok banner SPARCstation 2, Type 4 Keyboard ROM Rev. 2.2, 16 MB memory installed, Serial #426751 Ethernet address 8:0:20:e:fd:7c HostID 55411df8

* Type kb from the > PROM prompt on Sun4/nnn systems and press Return.

> kb Sun SPARCsystem 400. ROM Rev 4.1.1, 64MB memory installed, Serial #4206788. Ethernet address 8:0:20:10:37:c6, Host ID 244030BD.

If a system installed with Solaris 2.x software does not find the /kernel/unix boot program, you may need to change the boot-from setting in the PROM.

SPARC How to Change the boot-device PROM Setting

1. Halt the system using the init 0 command. The PROM prompt is displayed.

2. If the > PROM prompt is displayed, type n and press Return. The ok PROM prompt is displayed.

3. Type setenv boot-device diskn /kernel/unix and press Return. The boot-from setting is changed.

4. Type reset and press Return.

   The boot-device setting is written to the PROM.

See the monitor(1M) manual page for a complete list of PROM commands.

SPARC How to Run the Self-Test Program

From the ok PROM prompt:

* Type reset and press Return. The self-test program is run and the system is rebooted.

From the > PROM prompt on a Sun 4/nnn system:

* Type k2 and press Return The self-test program is run and the system is rebooted.

SPARC Boot Scenarios

Table 2-1 provides different boot scenarios for a SPARC system.

Table 2-1

Boot Type	Boot Command	This Type Of Boot Is Needed When...
Booting to multiuser state	ok boot > b	Changing kernel configuration information by modifying the /etc/system file.
Booting to single-user state	ok boot -s > b -s	Performing file system maintenance, such as performing a backup or restoring system data. Repairing a system file such as /etc/passwd.
Booting interactively	ok boot -a > b -a	Repairing a system configuration file such as /etc/system.
Booting after adding new hardware	See example on page 21	Adding hardware to the system. (Also know as a reconfiguration boot.)
Booting from a local CD-ROM drive	See example on page 13	Installing a new release of the operating system (this includes upgrading to a new operating system release). Repairing a critical system file which is causing system boot failure.
Booting from the network	See example on page 13	Installing a new release of the operating system from an installation server (including upgrades). Repairing an important system file when a local CD-ROM drive is not available.
Booting kadb	ok boot kadb > b kadb	Booting the kernel debugger (kadb) to track down a system problem.
Forcing a crash dump and rebooting	See example on page 15	Recovering from a hung system and you want to force a crash dump.

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SPARC - Booting brings the system to run level 3, multiuser level with resources shared, unless specified otherwise.

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SPARC Booting a System

If a system is powered off, turning it on starts the multiuser boot sequence. The following procedures show how to boot to different states from the ok PROM prompt. Type n to display the ok prompt on a newer Sun system if the prompt is >, and then follow the appropriate steps.

SPARC How to Boot to Multiuser State (Run Level 3)

Booting to multiuser state is usually done after halting the system or performing some system hardware maintenance task. This is the default boot level where all resources are available and users can log into the system.

* At the ok PROM prompt type boot and press Return. The automatic boot procedure starts, displaying a series of startup messages. The system is brought up in multiuser state.

SPARC How to Boot to Single-User State (Run Level S)

Booting to single-user state is usually done after performing some system maintenance task such as backing up the system. At this level only some file systems are mounted and users cannot log into the system.

1. At the ok PROM prompt type boot -s and press Return. The system boots to single-user state and prompts you for the root password.

ok boot -s INIT: SINGLE USER MODE Type Ctrl-d to proceed with normal startup, (or give root password for system maintenance): xxxxxxx

2. Type the root password and press Return.

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SPARC - To bring the system up to multiuser state after the system maintenance task is performed, press Control-d.

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SPARC How to Boot Interactively

You may want to boot interactively to make a temporary change to the system file or the kernel. Booting interactively lets you test your changes and recover easily if you have any problems.

1. At the ok PROM prompt, type boot -a and press Return. The boot program prompts you interactively.

2. Press Return to use the default kernel (/kernel/unix) as prompted, or type the name of the kernel to use for booting and press Return.

3. Press Return to use the default /etc/system file as prompted, or type the name of the system file and press Return.

4. Press Return to use the default modules directory path as prompted, or type the path for the modules directory and press Return.

5. Press Return to use the default /etc/path_to_inst file as prompted, or type an alternate file and press Return.

6. Press Return to use the default root file system type as prompted: ufs for local disk booting or nfs for diskless clients.

7. Press Return to use the default physical name of the root device as prompted, or type the device name.

SPARC Example: How to Boot Interactively

In this example, the default choices (shown in square brackets []) are accepted by pressing Return:

ok boot -a Enter filename [/kernel/unix]: (Copyright notice) Name of system file [/etc/system]: Name of default directory for modules [/kernel /usr/kernel]: Enter name of device instance number file [/etc/path_to_inst]: root filesystem type [ufs] Enter physical name of root device [/sbus@1,f8000000/esp@0,800000/sd@0,0:a]: Configuring network interfaces: le0 Hostname: pluto

(fsck messages) The system is coming up. Please wait (More messages) pluto login:

SPARC How to Boot from Local CD Drive or the Network

Booting from the local CD drive or the network is required when you have to repair an important system file that is preventing the system from booting successfully. This situation requires booting from a local CD-ROM drive or the network to recover. Recovering from a invalid /etc/passwd file is used as an example.

Substitute the device name of the file system to be repaired for the devicename variable identified in the procedures below. Refer to Chapter 1, "Accessing Devices on a SPARC System," if you need help identifying your device names.

1. Boot from the Solaris 2.x installation CD.

   a. Insert the Solaris 2.x installation CD into the CD caddy. b. Insert the CD caddy into the CD-ROM drive.

   c. Boot from the installation CD in single-user mode. Press Return.

ok boot cdrom -sw

2. Or, boot from the network if an installation server or remote CD drive is available.

ok boot net

3. Mount the root file system that has the invalid passwd file.

# mount /dev/dsk/devicename /a

4. Change to the newly mounted etc directory.

# cd /a/etc

5. Set the terminal type.

# TERM=sun # export TERM

6. Make the necessary change to the /etc/passwd file using an editor.

7. Change to the root directory.

8. Unmount the /a directory.

# umount /a

9. Reboot the system.

# init 6

SPARC How to Abort a Booting Process

Occasionally, you may need to abort the booting process. The specific abort key sequence depends on your keyboard type. For example, you can press Stop-A or L1-A. On terminals, press the Break key.

1. Type the abort key sequence for your system.

   The monitor displays the ok PROM prompt.

ok

2. Type the sync command at the ok prompt to synchronize the disks.

> n ok sync

3. Or, type the g0 command at the > prompt on a Sun 4/nnn system to synchronize the disks.

> g0

4. Once you see the syncing file systems. . . message, press the abort key sequence for your system again.

5. Type the appropriate boot command to restart the boot process.

SPARC How to Force a Crash Dump and Reboot the System

Use the following procedure if your system hangs and you want to force a crash dump. This procedure assumes that you have enabled the savecore feature. See Common Administration Tasks for information on the savecore feature.

1. Type the abort key sequence for your system.

   The monitor displays the ok PROM prompt.

ok

2. Type the sync command at the ok prompt to synchronize the disk and write the crash dump.

> n ok sync

3. Or, type the g0 command at the > prompt on a Sun 4/nnn system to synchronize the disk and write the crash dump.

> g0

After the crash dump is written to disk, the system will continue to reboot.

SPARC Displaying Boot Information

The dmesg command displays information that is provided during the boot process. The boot information is displayed as messages on the system console and provides helpful information for troubleshooting system boot problems.

This information is stored in the /var/adm/messages file.

An example of dmesg output is displayed below.