Which three statements are correct descriptions of SPARC M5-32 server design? (DCU = Domain Configuration Unit, CMU = CPU Memory Board Unit, IOU = I/O Switch Board)  

In a DCU that has 2x CMU, each CMU has 2x CPU, and each CPU has two PCIe root complexes; so you can access only eight PCIe slots (that is, 2x2x2) in that IOU. 

In a DCU that has 2x CMU, you need to install in position CMUO and CMU3 so that the root complexes of the two CPUs on CMUO can connect to IOBO and link to PCIe slots 1-8; and CMU3 can connect to IOB1 and link to PCIe slot9-l6. 

In a DCU that has 4x CMU, CMUO and CMU1 are connected to IOBO, and also linked to PCIe 1-8,but root complexes can work as fail over partners for high availability (the same applies to cmiw and CMU3 that connect to IOB1). 

EMS modules also need a PCIe root complex to control. 

In a DCU that has 2x CMU, installing in slots 0 and 1 is invalid.