NEC 320Lb-R manual Baseboard Management Controllers BMC, External Device Connectors

Baseboard Management Controllers (BMC)

Server management is concentrated in the Baseboard Management Controllers (BMC). The BMCs 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 modem, LAN, or direct connection to a manager system. Events monitored by the manager system include over-temperature and over- voltage conditions or fan failure.

Information on the Management Workstation Application (MWA) in the ESMPRO Suite User’s Guide on the ESMPRO CD-ROM.

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, or fan failure. 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 and diskette write-protect monitoring

!Controls Wake On LAN via Magic Packet support.

External Device Connectors

The external device I/O connectors located on the I/O panel board (see Figure 1-6) provide support for two USB ports that support a mouse/keyboard and a floppy diskette drive and two serial port connectors, and a VGA monitor port.

System Overview 1-29