The Server farm name (etsysLsnatServerfarmName) specifying the
Server farm to be assigned to this Virtual server entry. The
value of etsysLsnatVserverInetVersion must be consistent with
the value of etsysLsnatServerfarmInetVersion defined by this
etsysLsnatVserverServerfarmName. Setting this value requires
etsysLsnatVserverAdminStatus to be set to 'disabled'. A null
string results in no Virtual server Server farm entry being
assigned to this Virtual server.