HP-UX HB v13.00 Ch-02 - System Boot

HP-UX Handbook – Rev 13.00 Page 4 (of 14)

Chapter 02 System Boot

October 29, 2013

Introduction

Once a machine powers on, the firmware controls the system until the operating system (OS)

executes. The following steps need to be passed through before the system is fully operational:

Step 1 Processor Dependent Code (PDC)

Step 2 Initial System Loader (ISL)

Step 3 Loading the Kernel

Step 4 Starting the Subsystems

Step 5 Console Login

In case of an error during the boot up, you will be able to identify the cause if you exactly know

the standard boot process. This will be explained in this chapter. I recommend checking the

System Recovery Chapter, Chapter-04, for non-default boot mechanisms like single user mode,

quorum mode or maintenance mode.

Not every system boots the same. V-Class and Superdome systems do differently. Refer to the

Additional Information section in this current chapter for details.

Refer to the vPars Chapter, Chapter-17, to learn how a virtual partition is booted.

Refer to the Itanium Chapter, Chapter-21, to learn how an Itanium system is booted.

Step 1: Processor Dependent Code (PDC)

The PDC or system firmware is stored in the so called Stable Storage, a non-volatile piece of

memory located on the processor board. It is loaded and executed when the system is powered

on. It holds the addresses of primary and alternate boot device. The primary boot path will be

used if the user does not interrupt by pressing any key within 10 seconds (or the ESC key at

workstations):

Firmware Version 40.14

Duplex Console IO Dependent Code (IODC) revision 1

------------------------------------------------------------------------------

Processor Speed State CoProcessor State Cache Size

Number State Inst Data

--------- -------- --------------------- ----------------- ------------

0 360 MHz Active Functional 512 KB 1 MB

Central Bus Speed (in MHz) : 82