Sun Microsystems Enterprise 250 Owner's Manual page 239

POST status and error conditions are indicated by the general fault LED (
system front panel. The LED blinks slowly to indicate that POST is running. It
remains lit if POST detects a fault.
If a Sun Type-5 keyboard is attached, POST status and error indications are also
displayed via the four LEDs on the keyboard. When POST starts, all four keyboard
LEDs blink on and off simultaneously. After that, the Caps Lock LED blinks slowly
to indicate POST is running. If an error is detected, the pattern of the lit LEDs
provides an error indication. See "Error Indications" on page 242 for more
information.
If POST detects an error condition that prevents the system from booting, it will halt
operation and display the ok prompt. The last message displayed by POST prior to
the ok prompt indicates which part you need to replace.
Obtaining a Summary of POST Results
Use the .post command at the ok prompt to view a summary of POST results.
ok .post
System status: OK
CPU0: OK
CPU1: OK
SC-MP: OK
Psycho@1f: OK
Cheerio: OK
SCSI: OK
Mem Bank0: OK
Mem Bank1: OK
Mem Bank2: OK
Mem Bank3: OK
PROM: OK
NVRAM: OK
TTY: OK
SuperIO: OK
PCI Slots: OK
Chapter 11 Diagnostics and Troubleshooting
) on the
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