Server User Manual

28 Sun Fire V20z and Sun Fire V40z Servers, Server Management Guide • May, 2004
Baseboard Management Controller
In order to perform autonomous platform-management functions, the processor
runs embedded software or firmware. Together, the processor and its controlling
firmware are referred to as the Baseboard Management Controller (BMC), which is
the core of the IPMI structure. Tightly integrating an IPMI BMC and management
software with platform firmware facilitates a total management solution.
The BMC is a service processor integrated into the motherboard design, providing a
management solution independent of the main processor. The monitored server can
communicate with the BMC through one of three defined interfaces, which are based
on a set of registers shared between the platform and the BMC.
Note – In these servers, the SP has software that emulates a BMC.
The BMC is responsible for:
■ Managing the interface between server management software and platform
management hardware
■ Interfacing to the system sensors, such as fan speed and voltage monitors
■ Providing access to the system event log
■ Providing autonomous monitoring, event logging, and recovery control
■ Acting as a gateway between the management software and the IPMB/ICMB
■ Monitoring the system watchdog timer
■ Facilitating the remote-management tasks, even when the main server hardware
is in an inoperable state
The BMC provides the intelligence behind IPMI. In these servers, the SP serves as
the BMC, providing access to sensor data and events through the standard IPMI
interfaces.
Manageability
IPMI defines a mechanism for server monitoring and recovery implemented directly
in hardware and firmware. IPMI functions are available independent of the main
processors, BIOS, and operating system.
IPMI monitoring, logging, and access functions add a built-in level of manageability
to the platform hardware. IPMI can be used in conjunction with server-management
software running under the OS, which provides an enhanced level of manageability.
IPMI provides the foundation for smarter management of servers by providing a
methodology for maintaining and improving the reliability, availability and
serviceability of expensive server hardware.