Post And Openboot - Sun Microsystems Enterprise 6500 Reference Manual

9.3.3.1 History Log Option
To isolate an intermittent failure, it may be helpful to maintain a prtdiag history
log. Use the prtdiag command with the -l (log) option to send output to a log file
in the /var/adm directory.
9.3.3.2 Running prtdiag
To run prtdiag, type:
% /usr/platform/sun4u/sbin/prtdiag
9.3.4

POST and OpenBoot

POST and OpenBoot work together in the system to test and manage system
hardware.
POST resides in the OpenBoot PROM on each CPU/Memory+ board, I/O+ board,
and Disk board. When the system is turned on, or if a system reset is issued, POST
detects and tests buses, power supplies, boards, CPUs, SIMMs, and many board
functions. POST controls the status LEDs on the system front panel and all boards.
POST displays diagnostic and error messages on a console terminal, if available.
Only POST can configure the system hardware, and only POST can enable hot-
pluggable boards. If a new unit (board or modular power supply) is added to the
card cage after the system has booted, the new unit will not work until the system is
rebooted, at which time POST reconfigures the system, using the units that are
found in the system at that time.
Note – POST does not test drives or internal parts of SBus cards. To test these
devices, run OBP diagnostics manually after the system has booted. Refer to the
OpenBoot Command Reference manual for instructions.
OpenBoot provides basic environmental monitoring, including detection of
overheating conditions and out-of-tolerance voltages. For example, if an overheated
board is found, OpenBoot issues a warning message. If the temperature passes the
danger level, POST will put the overheated board(s) in low power mode.
OpenBoot also provides a set of commands and diagnostics at the ok prompt. For
example, you can use OpenBoot to set NVRAM variables that reserve a board or a
set of SIMMs for hot-sparing.
Chapter 9 Troubleshooting Overview 9-9