NEC 5800 manual System Board Management Controller BMC

1-22 System Overview

System Board Management Controller (BMC)

Server management is concentrated in the System Board Management Controller (BMC). The BMC and associated circuitry are powered from a 5Vdc standby voltage, which remains active when system power is switched off, but the ac power source is still on and connected.

The BMC supports the Management Workstation Application (MWA), which allows remote server management via a LAN, a modem, or direct connection to a manager system. Events monitored by the manager system include over-temperature and over-voltage conditions, fan failure, or chassis intrusion.

Information on the MWA may be found in the ESMPRO User's guide on the ESMPRO CD-ROM included with your server.

One major function of the BMC is to autonomously monitor system management events, and log their occurrence in the nonvolatile System Event Log (SEL). The events being monitored include overtemperature and overvoltage conditions, fan failure, or chassis intrusion. To enable accurate monitoring, the BMC maintains the nonvolatile Sensor Data Record (SDR), from which sensor information can be retrieved. The BMC provides an ISA host interface to SDR sensor information, so that software running on the server can poll and retrieve the server's current status.

The BMC performs the following:

!Monitors server board temperature and voltage

!Monitors processor presence and controls Fault Resilient Boot (FRB)

!Detects and indicates baseboard fan failure

!Manages the SEL interface

!Manages the SDR Repository interface

!Monitors the SDR/SEL timestamp clock

!Monitors the system management watchdog timer

!Monitors the periodic SMI timer

!Monitors the event receiver

!Controls secure mode, including video blanking, diskette write-protect monitoring, and front panel lock/unlock initiation

!Controls Wake On LAN via Magic Packet support.