The unique identifier of the primary server for this VTP
member and the associated database type.
There are two different VTP servers, the primary server
and the secondary server. When a local device is
configured as a server for a certain database type,
it becomes secondary server by default.
Primary server is an operational role under which a
server can initiate or change the VTP configuration of the
database type.
If this VTP member itself is the primary server, the
value of this object is the same as the value of
vtpDiscoverResultDeviceId of the instance.