Check the KB article: VMware KB: Storage Views multipath calculation
- "Software iSCSI has one adapter, which is bound to the VMkernel interfaces, and the esxcfg-mpath -l command shows 2 paths. You will always see Partial Redundancy status based on the way Multipathing Status displayed in vCenter is calculated. The same applies for NFS (and for any SAS controllers, if installed)."