ospf 配置NSSA为完全末节

我们知道OSPF默认配置NSSA之后，NSSA区域与次末节区域相似，阻止类型5的LSA进入，但可以接受类型7的LSA；并将其转换为类型5的LSA。

下面的实验将配置NSSA区域为完全末节，阻止类型3和类型4的域间路由进入NSSA区域
【实验拓扑】





【实验基本配置】

1、按照上图配置接口地址及OSPF
2、配置AREA1为NSSA区域
3、R6上配置静态路由160.1.60.0/24 到 Null0，重定向到OSPF中
4、R1上配置更高的路由器ID150.1.100.100，使得LSA7转换LSA5在R1上进行

【实验要求】
将R1与R4上的area 1配置为nssa完全次末节
在R6上将默认路由的cost值修改为100

【实验配置】

R1 & R4:
router ospf 1
area 1 nssa no-summary
area 1 default-cost 100

【实验验证】

配置之前--------------------------------------->>
R6#show ip route ospf
155.1.0.0/24 is subnetted, 2 subnets
O IA 155.1.0.0 [110/65] via 155.1.146.1, 00:46:49, GigabitEthernet0/1
150.1.0.0/16 is variably subnetted, 4 subnets, 2 masks
O IA 150.1.5.5/32 [110/66] via 155.1.146.1, 00:00:15, GigabitEthernet0/1
O 150.1.4.4/32 [110/2] via 155.1.146.4, 00:46:49, GigabitEthernet0/1
O 150.1.1.1/32 [110/2] via 155.1.146.1, 00:46:49, GigabitEthernet0/1
配置之后----------------------------------------->>
R6#show ip route ospf
150.1.0.0/16 is variably subnetted, 3 subnets, 2 masks
O 150.1.4.4/32 [110/2] via 155.1.146.4, 00:50:26, GigabitEthernet0/1
O 150.1.1.1/32 [110/2] via 155.1.146.1, 00:50:26, GigabitEthernet0/1
O*IA 0.0.0.0/0 [110/101] via 155.1.146.4, 00:00:02, GigabitEthernet0/1
[110/101] via 155.1.146.1, 00:00:02, GigabitEthernet0/1

实验总结：实验验证了域间路由消失，被替换为默认路由

【实验基本配置】

R1:
interface Fa 0/0
ip address 155.1.146.1 255.255.255.0
no shut
!
interface Serial 0/0
encapsulation frame-relay
no frame-relay inverse-arp
ip address 155.1.0.1 255.255.255.0
frame-relay map ip 155.1.0.5 105
frame-relay map ip 155.1.0.4 105
ip ospf priority 0
no shutdown
!
interface Loopback0
ip address 150.1.1.1 255.255.255.0
!
router ospf 1
router-id 150.1.100.100
network 155.1.146.1 0.0.0.0 area 1
network 150.1.1.1 0.0.0.0 area 1
network 155.1.0.1 0.0.0.0 area 0
area 1 nssa

R4:
interface Eth 0/1
ip address 155.1.146.4 255.255.255.0
!
interface Serial 0/0
encapsulation frame-relay
no frame-relay inverse-arp
ip address 155.1.0.4 255.255.255.0
frame-relay map ip 155.1.0.5 405
frame-relay map ip 155.1.0.1 405
ip ospf priority 0
!
interface Loopback0
ip address 150.1.4.4 255.255.255.0
!
router ospf 1
router-id 150.1.4.4
network 155.1.146.4 0.0.0.0 area 1
network 150.1.4.4 0.0.0.0 area 1
network 155.1.0.4 0.0.0.0 area 0
area 1 nssa

R5:
interface Serial 0/0
encapsulation frame-relay
no frame-relay inverse-arp
ip address 155.1.0.5 255.255.255.0
frame-relay map ip 155.1.0.4 504
frame-relay map ip 155.1.0.1 501
!
interface Loopback0
ip address 150.1.5.5 255.255.255.0
！
router ospf 1
router-id 150.1.5.5
network 150.1.5.5 0.0.0.0 area 0
network 155.1.0.5 0.0.0.0 area 0
neighbor 155.1.0.4
neighbor 155.1.0.1
area 1 nssa
R6:
interface Gig 0/1
ip address 155.1.146.6 255.255.255.0
!
interface Loopback0
ip address 150.1.6.6 255.255.255.0
!
ip route 160.1.60.0 255.255.255.0 Null0
router ospf 1
redistribute static subnets
router-id 150.1.6.6
network