Table 58 I/O Power Events That Light Diagnostic Panel LEDs (continued)
Notes
Source
Cause
Sample IPMI Events
Diagnostic
LEDs
(likely too
low)
Cooling Subsystem
There are six fan cooling zones within the server chassis that provide N+1 rotor redundancy for
the chassis using six identical dual fan assembly CRUs. Each dual fan assembly CRU is identified
by the chassis as fan 1-6 both for logging purposes and for fault identification. Note, however,
that three of the six total dual fan assemblies are considered as internal CRUs and are identified
by the chassis as fans 1, 2, and 3 on the diagnostic LED panel while the other three dual fan are
considered as external CRUs identified as fans 4, 5, and 6 and do not have LEDs on the diagnostic
LED panel.
External 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 the BMC turning on the
appropriate LEDs on the front and diagnostic LED panels.
Cooling Subsystem Behavior
The baseboard Management Controller (BMC) chip located on the Unified Core I/O board CRU
controls fan speed on ambient air temperatures, chip temperatures, server configuration, and
fan operation or failure. Air is drawn through the front of the chassis and pushed out the rear by
the cooling fans. (Note that you can display fan status remotely with the iLO 2 MP
ps
command.)
Within the server, temperature sensors report chassis temperatures to the BMC, which controls
fan speed based on this information.
lists the cooling subsystem events that light the diagnostic panel LEDs.
Table 59 Cooling Subsystem Events That Light Diagnostic Panel LEDs
Notes
Source
Cause
Sample IPMI Events
Diagnostic
LEDs
Cleared when fan is
replaced
BMC
Fan has either
previously failed or
is degrading
Type 02h, 0Ah:07h:01h
COOLING_UNIT_WARNING
Fans (1-3)
Cleared when fan is
replaced
BMC
Fan has failed and
no longer meets
Type 02h, 0Ah:07h:02h
COOLING_UNIT_FAILURE
Fans (1-3)
minimum
requirements
Common I/O Backplane (LBAs/Ropes/PDH/PCI-X Slots)
This subsection provides information on troubleshooting issues with the 8 public and 2 private
PCI-X slots.
I/O Subsystem Behaviors
The main role of the I/O subsystem is to transfer blocks of data and instruction words between
physical shared memory and virtual memory (system disks / disk array). The system boot is the
first time blocks of data and instructions words are transferred into physical shared memory from
a local disk / DVD or from a remote disk on another server through multiple LAN transfers. This
process is referred to as Direct Memory Access (DMA) and is initiated by I/O devices located in
core I/O or on Host Bus Adapter (HBA) I/O cards and does not involve any logical CPUs.
Cooling Subsystem
163