This reports the operational state, per CucsExtvmmRefOperState, of this uplink port profile's reference/link to its corresponding object in vCenter. Because the uplink profile only matters if vCenter's side of the mapping is actually up and correctly linked, this field on this specific profile is what tells you whether the DVS side of this uplink relationship is healthy, independent of the fabric interconnect's own physical port status. A refOperState of 'unresolved' here would mean this uplink profile no longer has a valid matching object in vCenter, likely because the DVS or uplink port group was changed or removed from the vCenter side.