思科模拟器 rip和ospf重分发出现问题：outer(config-router)#redistribute rip metric 1000 subnets 时，提示subnets出现错误

Question

左边是rip协议，右边是ospf协议，在中间的路由器重分发出现下列情况

Router(config)#router ospf 10

Router(config-router)#redistribute rip metric 1000 subnet
                                                   ^
% Invalid input detected at '^' marker.
    
Router(config-router)#redistribute rip metric 1000 ?
  <cr>
Router(config-router)#redistribute rip metric 1000 
% Only classful networks will be redistributed
Router(config-router)#redistribute rip ?
  metric       Metric for redistributed routes
  metric-type  OSPF/IS-IS exterior metric type for redistributed routes
  subnets      Consider subnets for redistribution into OSPF
  tag          Set tag for routes redistributed into OSPF
  <cr>

请问这是什么情况？怎么解决？