1、 将区域0R1的两条环回用acl引入到OSPF中来，将区域1R4的两条路由同样引入到OSPF1中来，查看R1的数据库表
<r1>dis ospf lsdb
OSPF Process 1 with Router ID 10.0.1.1
Link State Database
Area: 0.0.0.0
Type LinkState ID AdvRouter Age Len Sequence Metric
Router 10.0.3.3 10.0.3.3 501 48 80000005 0
Router 10.0.2.2 10.0.2.2 871 36 80000004 1
Router 10.0.1.1 10.0.1.1 502 48 8000000A 1
Network 10.0.13.1 10.0.1.1 502 32 80000002 0
Network 10.0.12.1 10.0.1.1 865 32 80000002 0
Sum-Net 10.0.34.0 10.0.3.3 488 28 80000001 1
Sum-Net 10.0.34.0 10.0.2.2 306 28 80000002 2
Sum-Net 10.0.24.0 10.0.2.2 861 28 80000001 1
Sum-Net 10.0.24.0 10.0.3.3 306 28 80000001 2
Sum-Asbr 10.0.4.4 10.0.2.2 210 28 80000001 1
Sum-Asbr 10.0.4.4 10.0.3.3 210 28 80000001 1
AS External Database
Type LinkState ID AdvRouter Age Len Sequence Metric
External 10.0.1.1 10.0.1.1 622 36 80000001 1
External 10.0.11.11 10.0.1.1 1380 36 80000001 1
External 10.0.4.4 10.0.4.4 211 36 80000001 1
External 10.0.44.44 10.0.4.4 211 36 80000001 1
可以看到有四条域外的路由引入
查看R1的路由表
Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Routing Tables: Public
Destinations : 17 Routes : 19
Destination/Mask Proto Pre Cost Flags NextHop Interface
10.0.1.1/32 Direct 0 0 D 127.0.0.1 LoopBack1
10.0.3.3/32 OSPF 10 1 D 10.0.13.3 GigabitEthernet 0/0/1
10.0.4.4/32 O_ASE 150 1 D 10.0.12.2 GigabitEthernet
0/0/0
O_ASE 150 1 D 10.0.13.3 GigabitEthernet
。
。
10.0.44.44/32 O_ASE 150 1 D 10.0.12.2 GigabitEthernet
0/0/0
O_ASE 150 1 D 10.0.13.3 GigabitEthernet
0/0/1
2、 将区域1配置NSSA区域
NSSA 10.0.4.4 10.0.4.4 62 36 80000001 1
NSSA 10.0.44.44 10.0.4.4 62 36 80000001 1
NSSA 0.0.0.0 10.0.3.3 75 36 80000001 1
NSSA 0.0.0.0 10.0.2.2 51 36 80000001 1
没有4 5类的LSA,成为了7类的LSA
查看路由表
<r4>dis ip routing-table
Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Routing Tables: Public
Destinations : 16 Routes : 17
Destination/Mask Proto Pre Cost Flags NextHop Interface
0.0.0.0/0 O_NSSA 150 1 D 10.0.34.3 GigabitEthernet
0/0/0
O_NSSA 150 1 D 10.0.24.2 GigabitEthernet
0/0/1
10.0.3.3/32 OSPF 10 1 D 10.0.34.3 GigabitEthernet
0/0/0
3、进一步的阻止三类LSA泛洪
配置完全NSSA
<r4>dis ospf lsdb
OSPF Process 1 with Router ID 10.0.4.4
Link State Database
Area: 0.0.0.1
Type LinkState ID AdvRouter Age Len Sequence Metric
Router 10.0.3.3 10.0.3.3 7 36 80000006 1
Router 10.0.4.4 10.0.4.4 6 48 80000012 1
Router 10.0.2.2 10.0.2.2 22 36 80000005 1
Network 10.0.24.4 10.0.4.4 20 32 80000002 0
Network 10.0.34.4 10.0.4.4 6 32 80000002 0
Sum-Net 0.0.0.0 10.0.2.2 31 28 80000001 1
Sum-Net 0.0.0.0 10.0.3.3 16 28 80000001 1
NSSA 10.0.4.4 10.0.4.4 1094 36 80000001 1
NSSA 10.0.44.44 10.0.4.4 1094 36 80000001 1
NSSA 0.0.0.0 10.0.3.3 16 36 80000001 1
NSSA 0.0.0.0 10.0.2.2 31 36 80000001 1
三类的LSA由缺省代替
实现备份将修改R3的cost为10
查看路由表
<r4>dis ip routing-table
Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Routing Tables: Public
Destinations : 13 Routes : 13
Destination/Mask Proto Pre Cost Flags NextHop Interface
0.0.0.0/0 OSPF 10 2 D 10.0.24.2 GigabitEthernet
0/0/1