Assigning separate IP Addresses to the each NIC for example:

iSCSI-R3
Eth 0 192.168.0.220
Eth 1 192.168.1.220

Microsoft Server

Eth 0 192.168.0.221
Eth 1 192.168.1.221

Please remove any bonds if you are using one for the assign NICs.

Also email support@open-e.com and we will send you a How to for MPIO.