300 Planning, Installing, and Managing the IBM System x3950 M26.1 BMC configuration optionsThe Baseboard Management Controller (BMC) in the x3850 M2 and x3950 M2systems is a service processor based on the Hitachi 2166 chip that complies withthe Intelligent Platform Management Interface, version 2.0 (IPMI v2.0)specification. The Intel specification document is available at:http://www.intel.com/design/servers/ipmi/ipmiv2_0_rev1_0_markup_2.pdfThe BMC stores information related to up to 512 events. After 512 events havebeen stored, the log must be cleared before further events are recorded. Afirst-in-first-out algorithm is not used here. The time it takes to fill the BMC logarea depends of the kind of events that have occurred.The BMC communicates with the RSA II through the Intelligent PlatformManagement Bus (IPMB) and controls the components about a whole set ofstandardized and system-specific sensors. The components communicate withthe BMC through an embedded Inter-Integrated Circuit (I²C) bus interface.Logged events that are defined as errors are reported, as follows: Into the RSA II event data store Through the BMC driver interface into the operation system and managementapplications Through error indicator LEDs on different components in the server By illuminating of the respectively error LED on the Light Path Diagnostic(LPD) panel, which you can pull out at the front of the x3850 M2 andx3950 M2 servers By IPMI messaging over LANThe BMC protects the server and powers the server off or prevents DC power-onin any of the following circumstances: At temperature of out-of-specification Invalid or wrong component installation Power voltage faultsTip: We recommend you save the BMC log before clearing it, in case theservice history is required. The logged events in the BMC can be transferredin-band to the Remote Supervisor Adapter II (RSA II) or to the operatingsystem through a driver.
