Powering The System On And Off; Power-On Self-Test - IBM pSeries 7311 D10 Service Manual

Powering the System On and Off

Power for the I/O subsystems is controlled by the attached processor subsystem and the System Power
Control Network (SPCN).
For information about procedures to power the system on and off, refer to the service guide of the
processor subsystem to which the I/O subsystem is attached.

Power-On Self-Test

After power is turned on and before the operating system is loaded, the system does a power-on self-test
(POST). The RIO loop that connects the I/O subsystems to the system unit is tested. Tests are also
performed on the installed adapters and devices in the I/O subsystems. If an error occurs during the
POST, an error code is displayed on the system operator panel LCD that indicates which part is failing and
which subsystem contains the error.
34 Eserver pSeries 7311 Model D10 and Model D20 Service Guide