The real DESCRIPTION field here is just the auto-generated stub "Cisco UCS fabric:FcVsanPortEp:portId managed object property", so it carries no real prose -- but the property name and its CucsFabricFcVsanPortEpPortId type tell you what it holds: It holds the physical port number this VSAN port endpoint sits on. Combined with slotId and switchId, this is one of the three coordinates that pin down exactly which physical FC or Ethernet port on the fabric interconnect this VSAN port endpoint corresponds to -- essential for an admin who needs to physically locate the cable to pull or reseat. On fabric interconnect A, this VSAN port endpoint might report portId 18, meaning it is physically the 18 port counting from the left on that module.