Diagnosing - IBM Power System E850C Technical Overview And Introduction

Concurrent access to the service processor menu of the ASMI
The ASMI provides management functionality for the server hardware through the service
processor. Access to these menus allows nondisruptive changes to system default
parameters, interrogation of service processor progress and error logs, and the ability to
set and reset service indicators (Light Path). You can also access all service processor
functions without having to power down the system to the standby state. The administrator
or service representative can dynamically access the menu and functionality from any web
browser-enabled console that is attached to the Ethernet support network, concurrently
with normal system operation. Some options, such as changing the hypervisor type, do
not take effect until the next boot.
Management of the interfaces for connecting uninterruptible power source systems to the
POWER processor-based systems and performing timed power-on (TPO) sequences.

4.5.4 Diagnosing

General diagnostic objectives are to detect and identify problems so that they can be resolved
quickly. The IBM diagnostic strategy includes the following elements:
Provide a common error code format that is equivalent to a system reference code,
system reference number, checkpoint, or firmware error code.
Provide fault detection and problem isolation procedures. Support a remote connection
ability that is used by the IBM Remote Support Center or IBM Designated Service.
Provide interactive intelligence within the diagnostic tests with detailed online failure
information while connected to IBM back-end systems.
Using the extensive network of advanced and complementary error detection logic that is built
directly into hardware, firmware, and operating systems, the Power E850C server can
perform considerable self-diagnosis.
Because of the FFDC technology that is designed in to all Power Systems servers,
re-creating diagnostic tests for failures or requiring user intervention is not necessary. Solid
and intermittent errors are designed to be correctly detected and isolated at the time that the
failure occurs. Runtime and boot time diagnostic tests fall into this category.
Boot time
When an IBM Power Systems server starts, the service processor initializes the system
hardware. Boot-time diagnostic testing uses a multitier approach for system validation. It
starts with managed low-level diagnostic tests that are supplemented with system firmware
initialization and configuration of I/O hardware, followed by OS-initiated software test routines.
To minimize boot time, the system determines which of the diagnostic tests are required to be
started to ensure correct operation. This determination is based on the way that the system
was powered off, or on the boot-time selection menu.
Host Boot IPL
In POWER8, the initialization process during IPL changed. The flexible service processor
(FSP) is no longer the only instance that initializes and runs the boot process. With POWER8,
the FSP initializes the boot processes, but on the POWER8 processor itself, one part of the
firmware is running and performing the Central Electronics Complex chip initialization. A new
component called the PNOR chip stores the Host Boot firmware and the Self Boot Engine
(SBE) is an internal part of the POWER8 chip itself that is used to boot the chip.
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IBM Power System E850C: Technical Overview and Introduction