I build up one iSCSI with MPIO in my lab, attached is draft diagram. My MPIO may not configure as well, due to even though I set Round Robin in my Windows Server 2012 iSCSI manager, I still noticed that only one NIC have traffic in the same time, and if I try to disconnect one cable, another cable will take around 30sec to get back on line.
Details:
Storage: HP P2000
Switch: CISCO 4900
Server: HP Bl460c g7
O.S: Windows Srv 2012 Data Center
Server NIC1 IP address: 10.0.0.5/24
Server NIC2 IP address: 10.0.1.5/24
HP P2000 Controller A NIC1 IP: 10.0.0.1/24
HP P2000 Controller B NIC1 IP: 10.0.1.1/24