If the OS is up, pressing the Power button for less than four seconds results in a graceful shutdown
of the operating system and a subsequent removal of system power. Pressing the Power button for
greater than four seconds results in a hard shutdown (system power removed). While the server is
booting (before the system has passed
EFI_EXIT_BOOT_SERVICES
), the BMC will power the
server off immediately on a button press, since there is no concept of soft shutdown in this state.
In the event that the OS is absent or hung, or that the manageability subsystem (specifically the
BMC) in the server is not responding, a greater than four second press of the Power button is
required to power down the system (a less than four second press on the Power button will have
no effect).
To ensure that the system powers up in a deterministic fashion, the Power button must be masked
for four seconds after a power-down.
Table 55
lists the power LED states.
Table 55 Power LED States
State
Flash Rate
LED Color
No AC power to the system
LED Off
System power is turned on
Steady
Green
System is shut down, but AC and housekeeping (standby) power
are active.
Steady
Amber
For HA and safety reasons, this LED is run directly off the power rails, rather than run under firmware
control.
Power Supply Power LED
There is a 1 Hz Flashing Green POWER LED (PWR), located on each power supply, which indicates
that AC is applied to the PSU, and that housekeeping voltages are available. This same LED
becomes Steady Green when all power outputs are available. If this LED enters a 1 Hz Flashing
Amber state, it indicates that the power supply has failed, and a replacement unit is necessary.
Table 56
lists the power supply conditions mapped to POWER LED states.
Table 56 Power Supply Conditions Mapped to Power LED States
Power Supply Condition
Power Supply Power
LED
No AC power applied to any PSUs
Off
No AC power applied to this PSU only
Off
AC present; housekeeping on
Flashing Green (Slow ~
1 Hz)
Power supply dc outputs On and OK
Steady Green
Power supply failure (includes overvoltage, overcurrent, overtemperature, and fan failure)
Flashing Amber (Slow
~ 1 Hz)
The Power Supply Power LED is visible on the power supply’s exterior face.
I/O VRM
Table 57
lists the I/O power events that light the diagnostic panel LEDs.
162
Troubleshooting
