Technical Product Specification

Intel® Server Boards S4600LH2/T2 TPS
Revision 2.0
68
6.7
Field Replaceable Unit (FRU) Inventory Device
The BMC implements the interface for logical FRU inventory devices as specified in the Intelligent Platform
Management Interface Specification, Version 2.0. This functionality provides commands used for accessing
and managing the FRU inventory information. These commands can be delivered through all interfaces.
The BMC provides FRU device command access to its own FRU device and to the FRU devices throughout
the server. The FRU device ID mapping is defined in the Platform Specific Information. The BMC controls the
mapping of the FRU device ID to the physical device.
6.8 System Event Log (SEL)
The BMC implements the system event log as specified in the Intelligent Platform Management Interface
Specification, Version 2.0. The SEL is accessible regardless of the system power state through the BMC's in-
band and out-of-band interfaces.
The BMC allocates 65,502 bytes (approx. 64 KB) of non-volatile storage space to store system events. The
SEL timestamps may not be in order. Up to 3,639 SEL records can be stored at a time. Any command that
results in an overflow of the SEL beyond the allocated space is rejected with an “Out of Space” IPMI
completion code (C4h).
Events logged to the SEL can be viewed using Intel’s SELVIEW utility, Embedded Web Server, and Active
System Console.
6.9 System Fan Management
The BMC controls and monitors the system fans. Each fan is associated with a fan speed sensor that detects
fan failure and may also be associated with a fan presence sensor for hot-swap support. For redundant fan
configurations, the fan failure and presence status determines the fan redundancy sensor state.
The system fans are divided into fan domains, each of which has a separate fan speed control signal and a
separate configurable fan control policy. A fan domain can have a set of temperature and fan sensors
associated with it. These are used to determine the current fan domain state.
A fan domain has three states: sleep, nominal, and boost. The sleep and boost states have fixed (but
configurable through OEM SDRs) fan speeds associated with them. The nominal state has a variable speed
determined by the fan domain policy. An OEM SDR record is used to configure the fan domain policy.
System fan speeds are controlled through pulse width modulation (PWM) signals, which are driven separately
for each domain by integrated PWM hardware. Fan speed is changed by adjusting the duty cycle, which is the
percentage of time the signal is driven high in each pulse