The Sun IPMI System Management Driver 2.1 allows communication between the Microsoft Windows host operating system and the ILOM service processor over an internal Keyboard Controller Style (KCS) interface. This driver is required for Microsoft Windows Server 2003 SP2 and earlier.
For later OS versions (including Microsoft Windows Server 2003 R2) the Microsoft-provided IPMI driver included in their Hardware Management Module provides the same functionality.
This driver must be installed before installing ipmitool. Refer to Installing the Sun IPMI System Management Driver 2.1 in Oracle Hardware Management Pack Installation Guide for information on installing the driver.