Initial System Loader (Isl) Environment; Invoking Isl From The Boot Console Handler - HP j6700 - Workstation Service Handbook

Boot Console Handler

Initial System Loader (ISL) Environment

Initial System Loader (ISL) Environment
The ISL environment provides the means to load the operating system (HP-UX)
environment. The ISL environment also provides an offline platform to execute optional
diagnostic and utility programs from a boot device when HP-UX does not load.
The ISL program is the first program loaded into main memory from an external medium
(LAN, disk, or tape) and launched by the initial program loader (IPL) routine from the
Boot Administration environment.
The ISL environment provides the following capabilities:
• Execute user-entered commands to modify boot device paths and boot options in stable
storage.
• Run offline diagnostic programs and utilities.
• Provide automatic booting of the HP-UX operating system after power-on or reset.

Invoking ISL from the Boot Console Handler

Perform the following steps to invoke ISL from the Boot Console Handler:
1. Follow the directions in the section "Accessing the Boot Console Handler" found in this
chapter, and type the following at the prompt:
Main Menu: Enter command > boot device [Enter]
You are prompted:
Interact with ISL (Y or N) > y [Enter]
2. Answering yes (y) causes the ISL to be loaded from the specified device. After a short
time, the following prompt appears on the screen:
ISL>
ISL is the program that actually controls the loading of the operating system. By
interacting with ISL, you can choose to load an alternate version of the HP-UX
operating system.
For example, if the usual kernel (/stand/vmunix) on the root disk has become
corrupted, and you wish to boot the workstation from the backup kernel
(/stand/vmunix.prev), type the following at the ISL> prompt:
ISL> hpux /stand/vmunix.prev [Enter]
132 Chapter 5