This read-only Unsigned64 value is a fault-aggregation bitmask that rolls up the current fault severities affecting this vNIC Ethernet Interface entry instance into a single number. Rather than having to enumerate every individual fault object, an admin (or a monitoring script) can check this single bitmask to quickly tell whether a vNIC Ethernet Interface entry instance currently has any outstanding faults and roughly how severe they are. If an Ethernet Interface entry attaching VLAN 130 to vNIC template 'vNIC-Templ-A' as its default (native) network developed a configuration problem, this fltAggr value would change from zero to a non-zero bitmask, which a monitoring system could use to trigger an alert without polling every underlying fault MO.