IBM RS/6000 44P - Manual (Page 81)

Service Processor Reboot/Restart Recovery
Reboot describes bringing the system hardware back up; for example, from a system
reset or power-on. The boot process ends when control passes to the operating system
process.
Restart describes activating the operating system after the system hardware is
reinitialized. Restart must follow a successful reboot.
Boot (IPL) Speed
When the server enters reboot recovery, slow IPL is automatically started, which gives
the POST an opportunity to locate and report any problems that may otherwise be
untested.
Failure During Boot Process
During the boot process, either initially after system power-on or upon reboot after a
system failure, the Service Processor monitors the boot progress. If progress stops, the
Service Processor can reinitiate the boot process (reboot) if enabled to do so. The
Service Processor can re-attempt this process according to the number of retries
selected in the Reboot/Restart Policy Setup Menu.
Failure During Normal System Operation
When the boot process completes and control transfers to the operating system (OS),
the service processor can monitor operating system activity (see the Set Surveillance
Parameters option in the SERVICE PROCESSOR SETUP MENU). If OS activity stops
due to a hardware-or software-induced failure, the service processor can initiate a
reboot/restart process based on the settings in the Service Processor Reboot/Restart
Policy Setup Menu and the OS automatic restart settings (see the operating system
documentation).
If you are using the AIX operating system, the menu item under SMIT for setting the
restart policy is Automatically Reboot After Crash (True/False). The default is False.
When the setting is True, and if the service processor parameter
″ Use OS-Defined
Restart Policy ″ is Yes (the default), Service Processor takes over for AIX to
reboot/restart after a hardware or surveillance failure.
Service Processor Reboot/Restart Policy Controls
The operating system’s automatic restart policy (see operating system documentation)
indicates the operating system response to a system crash. The service processor can
be instructed to refer to that policy by the Use OS-Defined Restart Policy setup menu.
Processor Boot-Time Deconfiguration (CPU Repeat-Gard)
Processor boot time deconfiguration allows for the removal of processors from the
system configuration at boot time. The objective is to minimize system failure or data
integrity exposure due to a faulty processor.
This function uses processor hardware Built-In Self-Test (BIST) and firmware Power-On
Self-Test (POST) to discover and isolate processor hardware failures during boot time.
Chapter 3. Using the Service Processor 63