The most basic operations for the System Administrator are the start up and the shut down of the operating system. This chapter discusses these operations and their associated topics. The processing of booting the operating system, either normally or interactively, differs between the operating systems; however, the run levels and methods for system shutdown are very similar.
Normal Startup
This section describes the simplified system start-up procedures for the HP-UX operating systems..
HP-UX
Automatic boot processes on various HP-UX systems follow a similar, general sequence.
The normal start-up process from a cold start executes three software components: the Processor Dependent Code (PDC), which initiates the Initial System Loader (ISL), which in turn starts the hpux secondary system loader for bootstrap. Finally, the loaded image displays numerous configuration and status messages and passes control to the init
process. At this point, the HP-UX init process reads the /etc/inittab file to complete initialization.
Processor Dependent Code
The Processor Dependent Code (PDC) is the firmware that implements all processor dependent functionality, including the initialization and self-test of the processor. The PDC is activated when the HP-UX system processor is powered on or when the system Reset button is pressed. This firmware gives the system administrator the option to override the autoboot sequence by pressing the Esc key. A message resembling the following usually appears on the console. (c) Copyright, Hewlett-Packard Company, All rights reserved.
PDC ROM rev. xxx.x xx MB of memory configured and tested. Selecting a system to boot.
To stop selection process, press and hold the ESCAPE key... On completion, the PDC loads and transfers control to the Initial System Loader utility. See the pdc (1M) reference page for additional information.
Initial System Loader utility
The Initial System Loader utility (ISL) is the operating system independent portion of the bootstrap processon an HP system. It is loaded and executed after self-test and initialization have completed successfully.When control is transferred to the ISL, an autoboot sequence takes place, which allows a complete bootstrapoperation to occur without intervention from the operator. While an auto-boot sequence occurs, ISL finds and executes the autoexecute file that requests that hpux, the next component, be run with the appropriate arguments. The console displays messages like the following: Booting from: scsi.x HP aaaa Hard booted. ISL Revision A.xx.xx date ISL booting hpux boot disk(;0)/stand/vmunix
See the isl (1M) reference page for additional information.
Secondary System Loader Utility, hpux
The Secondary System Loader, hpux, displays the load image’s device file, as well as the TEXT size, DATA size, the BSS size, and start address of the load image before control passes to the image. Here is an example of the hpux output:
Booting disk(scsi.x;0)/stand/vmunix
966616+397312+409688 start 0x6c50
The setboot utility
The HP-UX operating system offers a utility that enables you to display and modify variables that influence the boot sequence, so that you do not need to bring the system down. These variables reside in an area of high-reliability memory called “stable storage.” This storage contains the boot path information along with other critical file system parameters even if the storage card is removed from the backplane. After the initial memory controller is initialized, the processor-dependent code (PDC) accesses stable storage to determine the
boot device and console selection process; this information consists of the following:
• the primary boot path
• the alternate boot path
• whether the autosearch sequence is enabled or disabled
• whether the autoboot sequence is enabled or disabled.
The setboot utility provides option flags for setting this information. To read the current values, enter the
setboot utility without any options or parameters, as shown here:
# setboot
Primary bootpath : 10/0/15/0.6.0
Alternate bootpath : 10/0/14/0.0.0
Autoboot is ON (enabled)
Autosearch is ON (enabled)
Interactive Boot
With an interactive boot, you can specify a boot device or kernel different from the default. This is especially useful for testing a newly configured kernel. Also, you have the ability to interact with the firmware to display or set the system firmware parameters
HP-UX
An interactive boot is sometimes referred to as a single-user boot or an attended mode boot in HP-UX parlance. Pressing the Esc key during the boot process halts the automatic boot sequence. You are able to interact with the PDC, which displays the Boot Console User Interface main menu, as shown here. Selecting a system to boot.
To stop selection process, press and hold the ESCAPE key.
Selection process stopped.
Searching for Potential Boot Devices.
To terminate search, press and hold the ESCAPE key.
Device Selection Device Path Device Type
-------------------------------------------------------------
P0 scsi.x.0 device type for p0
P1 scsi.y.0 device type for p1
P2 lan.ffffff-ffffff.f.f device type for p2
b) Boot from specified device
s) Search for bootable devices
a) Enter Boot Administration mode
x) Exit and continue boot sequence
Select from menu:
The system automatically searches the SCSI busses, the local area network (LAN), and other possible interfaces for all potential boot devices and lists them in table form.
The PDC also provides a menu of options in the event you wanted to perform some task other than boot the system. You need to specify option b to boot the system. You also need to specify the device shown in the Device Selection column that contains the program to be booted and the name of that program, usually isl. The Initial System Loader utility controls the loading of the operating system. The following example shows how to boot the ISL from device P2:Select from menu: b p0 isl
The system displays first a few messages, then the ISL prompt. At this point, you have the following capabilities:
• Booting to single user mode:
ISL>hpux -is
• Booting to multi-user mode (without network services):
ISL>hpux -i2
• Booting another kernel, possibly with a modified configuration:
ISL>hpux vmunix.trial
• Booting from another section of the root disk
• Booting from another disk
ISL>hpux (2.0.0.0)/stand/vmunix
• Booting from LAN:
ISL>hpux lan(32)/stand/vmunix
• Listing the contents of the /stand directory on the root disk:
ISL>hpux ll /stand
See the hpux (1M) reference page for additional information.
To continue booting to single-user mode, enter the following command:
ISL>hpux -is
The i option to the hpux utility passes its argument to the init process; this argument specifies the run level; In this example, the string s indicates single user mode. Continuing the example, the output from the hpux utility resembles the following:
Boot : disk(scsi.x;0)/stand/vmunix
xxxxxx+yyyyyy+zzzzzz start 0xnnnn
Kernel Startup Messages Omitted
INIT: Overriding default level with level ‘s’
INIT: SINGLE USER MODE
WARNING: YOU ARE SUPERUSER!!
#
Usually the system administrator invokes the init utility with run level 2 or 3 to start multi-user mode.
Run Levels
The following table illustrates the similarity of the HP-UX and Tru64 UNIX run levels. Both operating systems allow the system administrator to define custom run levels.
Run Level HP-UX
· 0 Halt
· S Single User State with only essential system services (NOTE: with this run level the console is maintained at the tty where init was run).
· s Single User State with only essential system services
· 1 Starts a subset of essential system processes; the file systems in /etc/fstab are mounted. It can also be used to erform system administration tasks.
· 2 The operating mode is typically called "multi-user state". This mode allows all
users to access the system. Network and NFS client are enabled
· 3 Multi-User Mode. NFS and X Server enabled. In this mode, NFS file systems can
be exported, as required for NFS servers.
· 4 For HP VUE users. In this mode, HP VUE is active.
· 5 Definable
· 6 Definable
· 7 Definable
· 8 Definable
· 9 Definable
System Shutdown
In hpux operating systems, you can use either the shutdown command or a graphical utility to shutdown the system.
The shutdown command
The most often used options (-h and -r) for shutdown
Graphical Utilities
HP-UX
You can shut down the system through the HP-UX SAM utility as follows:
1. Select the Routine Tasks icon.
HP-UX
-h Shut down system and halt. -h Shut down the system or cluster and halt.
-r Shut down the system and reboot -r Shut down the system and reboot.
-y Do not require any interactive responses.
-b Send shutdown message to the rwalld daemon on remote client hosts that have mounted NFS file systems.
-o In a diskless cluster environment,shutdown the server only, but do not reboot the clients.
-f Fast shut down.
-k Send message to users without shutting down the system.
-n Bypasses normal disk synchronization before shutting down.
-s Executes the stop entry point of the run-level transition scripts in
/sbin/rc0.d/Knn_name,
/bin/rc2.d/Knn_name, and
/sbin/rc0d/K45syslog.
The Routine Tasks window opens.
2. Select the System Shutdown icon. The System Shutdown dialog box opens.
3. Select the appropriate options, then select OK.
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