Troubleshooting The Cooling Subsystem; Cooling Subsystem Behavior - HP Integrity rx2800 i4 User Manual

The power button has a momentary switch (as opposed to a latching switch) that is recessed or
covered to prevent accidental activation or deactivation.
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 five seconds results in a hard shutdown (system power removed). While the server is
booting (before the system has passed UEFI_EXIT_BOOT_SERVICES), the iLO MP immediately
powers the server off 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
iLO MP) in the server is not responding, a greater than five-second press of the power button is
required to power off the system (a less than five second press on the power button has no effect
in this event).
To ensure that the system powers up in a deterministic fashion, the power button must be masked
for five seconds after a power-down.
Table 33 Power LED States
Definition
No AC power to the system
System power is turned on
System is shut down, but AC and housekeeping (standby) power are
active.
For high availability and safety reasons, this LED runs off the power rails, rather than under firmware
control.

Troubleshooting the cooling subsystem

The fans located within the server provide N+1 redundancy for the server using six identical dual
fan assembly CRUs. In turn, each dual fan assembly CRU provides additional N+1 redundancy
for the fan cooling zone it controls. Each dual fan assembly CRU is identified by the server as fans
1 through 6 both for logging purposes and for fault identification on the diagnostic LED panel.
Cooling fan CRU failures are identified visually by a single green LED on the dual fan assembly
CRU that is turned on when one or both of the fans fail; logged as an IPMI event by fan sensor
logic; and identified as a fan assembly CRU failure by iLO 3 turning on the appropriate LEDs on
the System Insight Display panel.

Cooling subsystem behavior

The iLO 3 MP controls fan speed on ambient air temperatures, chip temperatures, server
configuration, and fan operation or failure. Air is drawn through the front of the server and pushed
out the rear by the cooling fans. You can display fan status remotely with the iLO 3 MP ps command.
Within the server, temperature sensors report server temperatures to iLO 3, which controls fan
speed based on this information.
Table 34 Cooling subsystem events that illuminate SID LEDs
Diagnostic
LEDs
Fans (1-6)
Fans (1-6)
84 Troubleshooting
Sample IPMI Events
Type 02h, 0Ah:07h:01h
COOLING_UNIT_WARNING
Type 02h, 0Ah:07h:02h
COOLING_UNIT_FAILURE
Flash rate
LED Off
Steady
Steady
Cause Source
Fan has either iLO 3
previously failed or
is degrading
Fan has failed and iLO 3
no longer meets
minimum
requirements
LED color
Green
Amber
Notes
Cleared when fan is
replaced
Cleared when fan is
replaced
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