In a SPARC M8-8 or a SPARC M7-8 server that is configured with two PDomains, each static PDomain consists of four of the eight CMIOUs in the chassis; one PDomain consists of cmiou0-cmiou3, the other consists of cmiou4-cmiou7.
Two service processors (SP0 and SP1) achieve redundancy with two SPMs each that are assigned to different static PDomains. SPM0 on each SP manages one static PDomain (DCU_0) in the chassis, while SPM1 on each SP manages the other static PDomain (DCU_1).
Oracle ILOM identifies one of the SPMs from each SP as the Active SP to manage activity on the static PDomain. The other SPM on the SP runs Oracle ILOM, but remains inactive unless the Active SP can no longer manage the hardware. In this case, the inactive SPM assumes the Active SP role.
You cannot specify which SPMs will serve as the Active SP, but you can request that Oracle ILOM should assign a new SPM to serve each role. You might do this when, for example, you are replacing an SP.