ABB路由器和A路由器之间运行OSPF协议，B路由器通过OSPF发布三条静态路由到A路由器，静态路由的目的网段为5.5.5.5，6.6.6.6，7.7.7.7，类型为第一类外部路由，A路由器学到的5.5.5.5.的cost值比6.6.6.6和7.7.7.7的cost值小。配置如下：B路由器routerid2.2.2.2#interfaceEthernet4/2/0ipaddress11.11.11.12255.255.255.0#aclnumber1rule0permitsource5.5.5.50#aclnumber2rule0denysource5.5.5.50rule1permit#ospfimport-routestaticcost100type1route-policycost#area0.0.0.0network2.2.2.20.0.0.0network11.11.11.00.0.0.255#route-policycostpermitnode10if-matchacl1applycost10route-policycostpermitnode20if-matchacl2#iproute-static5.5.5.5255.255.255.255NULL0preference60iproute-static6.6.6.6255.255.255.255NULL0preference60iproute-static7.7.7.7255.255.255.255NULL0preference60#A路由器配置：routerid1.1.1.1!interfaceEthernet3/1/0ipaddress11.11.11.11255.255.255.0!interfaceLoopBack1/0/0ipaddress1.1.1.1255.255.255.255!routerospfnetwork1.1.1.10.0.0.0area0.0.0.0network11.11.11.00.0.0.255area0.0.0.0!end在路由器A使用showiproute查看路由表如下：RoutingTables:Destination/MaskProtoPreMetricNexthopInterface1.1.1.1/32Direct00127.0.0.1InLoopBack02.2.2.2/32OSPF10156311.11.11.12Ethernet3/1/05.5.5.5/32O_ASE1501111.11.11.12Ethernet3/1/06.6.6.6/32O_ASE15010111.11.11.12Ethernet3/1/07.7.7.7/32O_ASE15010111.11.11.12Ethernet3/1/011.11.11.0/24Direct0011.11.11.11Ethernet3/1/011.11.11.11/32Direct00127.0.0.1InLoopBack0在路由策略中使用acl访问列表，默认的是denyall，如果路由器上使能防火墙，即firewallenable，系统缺省的是permitall，