Intelligent Platform Management Interface - IPMI Components - Baseboard Management Controller

Baseboard Management Controller

The baseboard management controller (BMC) is the intelligence in the IPMI architecture. It is a specialized microcontroller embedded on the motherboard of a computer, generally a server. The BMC manages the interface between system management software and platform hardware.

Different types of sensors built into the computer system report to the BMC on parameters such as temperature, cooling fan speeds, power status, operating system (OS) status, etc. The BMC monitors the sensors and can send alerts to a system administrator via the network if any of the parameters do not stay within preset limits, indicating a potential failure of the system. The administrator can also remotely communicate with the BMC to take some corrective action such as resetting or power cycling the system to get a hung OS running again. These abilities save on the total cost of ownership of a system.

Physical interfaces to the BMC include SMBus buses, an RS-232 serial console, address and data lines and an Intelligent Platform Management Bus (IPMB), that enables the BMC to accept IPMI request messages from other management controllers in the system.

A direct serial connection to the BMC is not encrypted as the connection itself is secure. Connection to the BMC over LAN may or may not use encryption depending on the security concerns of the user.