Description: To add a new entry to the mdgGatewayTable, set this object to primary(2) or other(3) for an IP address which is not already in the table. The primary entry will be used first, if it is reachable. Otherwise, one of the other entries will be used. Setting one entry to primary(2) causes any previous primary entry to change to other(3). To remove an entry from the table, set this object to invalid(1). Changing an existing entry from primary(2) to other(3) is not allowed. If the value of this object is updated, the corresponding entry of the ipRouteTable (mibII) will be updated and vice versa.