OSPF 多区域配置

实验拓扑及网络规划:如上图

实验任务和目标：
任务1.按照实验要求连接拓扑。
任务2.完成所有网络基本IP配置【环回除外】，并测试网络联通性。
任务3.启动骨干区域AREA 0的OSPF进程。
任务4.启动末节区域AREA 1的OSPF进程。
任务5.启动完全末节区域AREA12的OSPF进程。
任务6.测试网络连通性，观察路由表，观察内置表，观察邻居表，观察BORD-ROUTER表【截图验证】
任务7.修改AREA 12的完全末节区域为标准区域，配置环回接口。
任务8.发布OSPF AS外部直连环回接口到OSPF AS中，并配置ROUTER 6的缺省路由，并测试ROUTER 7与ROUTER 6的环回连通性【截图验证】。
任务9.观察路由表，观察BORD-ROUTER表【截图验证】。

实验操作过程及配置说明：

任务1.按照实验要求连接拓扑。



任务2.完成所有网络基本IP配置【环回除外】，并测试网络联通性。

r1#show ip int bri
Interface IP-Address OK? Method Status Protocol
Serial0/0 192.168.1.1 YES manual up up
Serial0/1 192.168.1.5 YES manual up up
Serial0/2 192.168.1.9 YES manual up up
Serial0/3 10.1.1.2 YES manual up up

r2#show ip int bri
Interface IP-Address OK? Method Status Protocol
Serial0/0 192.168.1.2 YES manual up up
Serial0/1 192.168.1.6 YES manual up up
Serial0/2 unassigned YES unset administratively down down
Serial0/3 unassigned YES unset administratively down down
Ethernet1/0 unassigned YES unset administratively down down
Ethernet1/1 192.168.1.13 YES manual up up
Ethernet1/2 unassigned YES unset administratively down down

r3#show ip int bri
Interface IP-Address OK? Method Status Protocol
Serial0/0 unassigned YES unset administratively down down
Serial0/1 unassigned YES unset administratively down down
Serial0/2 192.168.1.10 YES manual up up
Serial0/3 unassigned YES unset administratively down down
Ethernet1/0 unassigned YES unset administratively down down
Ethernet1/1 192.168.1.14 YES manual up up
Ethernet1/2 unassigned YES unset administratively down down
Ethernet1/3 unassigned YES unset administratively down down

r4#show ip int bri
Interface IP-Address OK? Method Status Protocol
Serial0/0 192.168.12.1 YES manual up up
Serial0/1 192.168.12.5 YES manual up up
Serial0/2 192.168.12.9 YES manual up up
Serial0/3 10.12.12.2 YES manual up up

r5#show ip int bri
Interface IP-Address OK? Method Status Protocol
Serial0/0 192.168.12.2 YES manual up up
Serial0/1 192.168.12.6 YES manual up up
Serial0/2 unassigned YES unset administratively down down
Serial0/3 unassigned YES unset administratively down down
Ethernet1/0 unassigned YES unset administratively down down
Ethernet1/1 192.168.12.13 YES manual up up
Ethernet1/2 unassigned YES unset administratively down down
Ethernet1/3 unassigned YES unset administratively down down

r6#show ip int bri
Interface IP-Address OK? Method Status Protocol
Serial0/0 unassigned YES unset administratively down down
Serial0/1 unassigned YES unset administratively down down
Serial0/2 192.168.12.10 YES manual up up
Serial0/3 unassigned YES unset administratively down down
Ethernet1/0 unassigned YES unset administratively down down
Ethernet1/1 192.168.12.14 YES manual up up
Ethernet1/2 unassigned YES unset administratively down down
Ethernet1/3 unassigned YES unset administratively down down

r7#show ip int bri
Interface IP-Address OK? Method Status Protocol
Serial0/0 unassigned YES unset administratively down down
Serial0/1 10.1.1.1 YES manual up up
Serial0/2 10.12.12.1 YES manual up up
Serial0/3 unassigned YES unset administratively down down

任务3.启动骨干区域AREA 0的OSPF进程。

r7(config)#router ospf 10

r7(config-router)#router-id 7.7.7.7
r7(config-router)#network 10.1.1.1 0.0.0.0 a 0
r7(config-router)#network 10.12.12.1 0.0.0.0 a 0
r7(config-router)#end

r1(config)#router ospf 10
r1(config-router)#router-id 1.1.1.1
r1(config-router)#network 10.1.1.2 0.0.0.0 a 0
r1(config-router)#end

r4(config)#router ospf 10
r4(config-router)#router-id 4.4.4.4
r4(config-router)#network 10.12.12.2 0.0.0.0 a 0
r4(config-router)#end

任务4.启动末节区域AREA 1的OSPF进程。（stub）

r1(config)#router ospf 10
r1(config-router)#network 192.168.1.1 0.0.0.0 area 1
r1(config-router)#network 192.168.1.5 0.0.0.0 area 1
r1(config-router)#network 192.168.1.9 0.0.0.0 area 1
r1(config-router)#network 10.1.1.2 0.0.0.0 area 0
r1(config-router)#area 1 stub

r2(config)#router ospf 10
r2(config-router)#network 192.168.1.2 0.0.0.0 area 1
r2(config-router)#network 192.168.1.6 0.0.0.0 area 1
r2(config-router)#network 192.168.1.13 0.0.0.0 area 1
r2(config-router)#area 1 stub

r3(config)#router ospf 10
r3(config-router)#network 192.168.1.10 0.0.0.0 area 1
r3(config-router)#network 192.168.1.14 0.0.0.0 area 1
r3(config-router)#area 1 stub

r1#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

10.0.0.0/24 is subnetted, 2 subnets
O 10.12.12.0 [110/128] via 10.1.1.1, 00:46:23, Serial0/3
C 10.1.1.0 is directly connected, Serial0/3
192.168.1.0/30 is subnetted, 4 subnets
C 192.168.1.8 is directly connected, Serial0/2
O 192.168.1.12 [110/74] via 192.168.1.10, 00:45:31, Serial0/2
[110/74] via 192.168.1.6, 00:45:31, Serial0/1
[110/74] via 192.168.1.2, 00:45:31, Serial0/0
C 192.168.1.0 is directly connected, Serial0/0
C 192.168.1.4 is directly connected, Serial0/1

r2#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is 192.168.1.5 to network 0.0.0.0

10.0.0.0/24 is subnetted, 2 subnets
O IA 10.12.12.0 [110/192] via 192.168.1.5, 00:45:38, Serial0/1
[110/192] via 192.168.1.1, 00:45:38, Serial0/0
O IA 10.1.1.0 [110/128] via 192.168.1.5, 00:45:38, Serial0/1
[110/128] via 192.168.1.1, 00:45:38, Serial0/0
192.168.1.0/30 is subnetted, 4 subnets
O 192.168.1.8 [110/74] via 192.168.1.14, 00:45:38, Ethernet1/1
C 192.168.1.12 is directly connected, Ethernet1/1
C 192.168.1.0 is directly connected, Serial0/0
C 192.168.1.4 is directly connected, Serial0/1
O*IA 0.0.0.0/0 [110/65] via 192.168.1.5, 00:45:38, Serial0/1
[110/65] via 192.168.1.1, 00:45:38, Serial0/0

r3#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is 192.168.1.9 to network 0.0.0.0

10.0.0.0/24 is subnetted, 2 subnets
O IA 10.12.12.0 [110/192] via 192.168.1.9, 00:45:38, Serial0/2
O IA 10.1.1.0 [110/128] via 192.168.1.9, 00:45:38, Serial0/2
192.168.1.0/30 is subnetted, 4 subnets
C 192.168.1.8 is directly connected, Serial0/2
C 192.168.1.12 is directly connected, Ethernet1/1
O 192.168.1.0 [110/74] via 192.168.1.13, 00:45:38, Ethernet1/1
O 192.168.1.4 [110/74] via 192.168.1.13, 00:45:38, Ethernet1/1
O*IA 0.0.0.0/0 [110/65] via 192.168.1.9, 00:45:38, Serial0/2

任务5.启动完全末节区域AREA12的OSPF进程。（totally stubby）

r4(config)#router ospf 10
r4(config-router)#network 192.168.12.1 0.0.0.0 area 12
r4(config-router)#network 192.168.12.5 0.0.0.0 area 12
r4(config-router)#network 192.168.12.9 0.0.0.0 area 12
r4(config-router)#network 10.12.12.2 0.0.0.0 area 0
r4(config-router)#area 12 stub no-summary

r5(config)#router ospf 10
r5(config-router)#network 192.168.12.2 0.0.0.0 area 12
r5(config-router)#network 192.168.12.6 0.0.0.0 area 12
r5(config-router)#network 192.168.12.13 0.0.0.0 area 12
r5(config-router)#area 12 stub

r6(config)#router ospf 10
r6(config-router)#network 192.168.12.10 0.0.0.0 area 12
r6(config-router)#network 192.168.12.14 0.0.0.0 area 12
r6(config-router)#area 12 stub

r5#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is 192.168.12.5 to network 0.0.0.0

192.168.12.0/30 is subnetted, 4 subnets
C 192.168.12.4 is directly connected, Serial0/1
C 192.168.12.0 is directly connected, Serial0/0
C 192.168.12.12 is directly connected, Ethernet1/1
O 192.168.12.8 [110/74] via 192.168.12.14, 00:00:00, Ethernet1/1
O*IA 0.0.0.0/0 [110/65] via 192.168.12.5, 00:00:00, Serial0/1
[110/65] via 192.168.12.1, 00:00:00, Serial0/0

r6#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is 192.168.12.9 to network 0.0.0.0

192.168.12.0/30 is subnetted, 4 subnets
O 192.168.12.4 [110/74] via 192.168.12.13, 00:08:01, Ethernet1/1
O 192.168.12.0 [110/74] via 192.168.12.13, 00:08:01, Ethernet1/1
C 192.168.12.12 is directly connected, Ethernet1/1
C 192.168.12.8 is directly connected, Serial0/2
O*IA 0.0.0.0/0 [110/65] via 192.168.12.9, 00:08:01, Serial0/2

任务6.测试网络连通性，观察路由表，观察内置表，观察邻居表，观察BORD-ROUTER表【截图验证】

r6#p 192.168.1.14

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.14, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 76/109/136 ms

r6#p 192.168.1.6

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.6, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 64/89/148 ms

r5#ping 192.168.1.14

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.14, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 56/120/172 ms
r5#ping 192.168.1.6

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.6, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 60/119/152 ms

r1#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

192.168.12.0/30 is subnetted, 4 subnets
O IA 192.168.12.4 [110/192] via 10.1.1.1, 00:17:58, Serial0/3
O IA 192.168.12.0 [110/192] via 10.1.1.1, 00:18:07, Serial0/3
O IA 192.168.12.12 [110/202] via 10.1.1.1, 00:15:13, Serial0/3
O IA 192.168.12.8 [110/192] via 10.1.1.1, 00:17:58, Serial0/3
10.0.0.0/24 is subnetted, 2 subnets
O 10.12.12.0 [110/128] via 10.1.1.1, 00:18:07, Serial0/3
C 10.1.1.0 is directly connected, Serial0/3
192.168.1.0/30 is subnetted, 4 subnets
C 192.168.1.8 is directly connected, Serial0/2
O 192.168.1.12 [110/74] via 192.168.1.10, 01:32:41, Serial0/2
[110/74] via 192.168.1.6, 01:32:41, Serial0/1
[110/74] via 192.168.1.2, 01:32:41, Serial0/0
C 192.168.1.0 is directly connected, Serial0/0
C 192.168.1.4 is directly connected, Serial0/1

r2#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is 192.168.1.5 to network 0.0.0.0

192.168.12.0/30 is subnetted, 4 subnets
O IA 192.168.12.4 [110/256] via 192.168.1.5, 00:16:42, Serial0/1
[110/256] via 192.168.1.1, 00:16:42, Serial0/0
O IA 192.168.12.0 [110/256] via 192.168.1.5, 00:16:51, Serial0/1
[110/256] via 192.168.1.1, 00:16:51, Serial0/0
O IA 192.168.12.12 [110/266] via 192.168.1.5, 00:13:57, Serial0/1
[110/266] via 192.168.1.1, 00:13:57, Serial0/0
O IA 192.168.12.8 [110/256] via 192.168.1.5, 00:16:42, Serial0/1
[110/256] via 192.168.1.1, 00:16:42, Serial0/0
10.0.0.0/24 is subnetted, 2 subnets
O IA 10.12.12.0 [110/192] via 192.168.1.5, 01:31:26, Serial0/1
[110/192] via 192.168.1.1, 01:31:26, Serial0/0
O IA 10.1.1.0 [110/128] via 192.168.1.5, 01:31:26, Serial0/1
[110/128] via 192.168.1.1, 01:31:26, Serial0/0
192.168.1.0/30 is subnetted, 4 subnets
O 192.168.1.8 [110/74] via 192.168.1.14, 01:31:29, Ethernet1/1
C 192.168.1.12 is directly connected, Ethernet1/1
C 192.168.1.0 is directly connected, Serial0/0
C 192.168.1.4 is directly connected, Serial0/1
O*IA 0.0.0.0/0 [110/65] via 192.168.1.5, 01:31:30, Serial0/1
[110/65] via 192.168.1.1, 01:31:30, Serial0/0

r3#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is 192.168.1.9 to network 0.0.0.0

192.168.12.0/30 is subnetted, 4 subnets
O IA 192.168.12.4 [110/256] via 192.168.1.9, 00:16:53, Serial0/2
O IA 192.168.12.0 [110/256] via 192.168.1.9, 00:17:03, Serial0/2
O IA 192.168.12.12 [110/266] via 192.168.1.9, 00:14:09, Serial0/2
O IA 192.168.12.8 [110/256] via 192.168.1.9, 00:16:53, Serial0/2
10.0.0.0/24 is subnetted, 2 subnets
O IA 10.12.12.0 [110/192] via 192.168.1.9, 01:31:31, Serial0/2
O IA 10.1.1.0 [110/128] via 192.168.1.9, 01:31:31, Serial0/2
192.168.1.0/30 is subnetted, 4 subnets
C 192.168.1.8 is directly connected, Serial0/2
C 192.168.1.12 is directly connected, Ethernet1/1
O 192.168.1.0 [110/74] via 192.168.1.13, 01:31:31, Ethernet1/1
O 192.168.1.4 [110/74] via 192.168.1.13, 01:31:31, Ethernet1/1
O*IA 0.0.0.0/0 [110/65] via 192.168.1.9, 01:31:32, Serial0/2

r4#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

192.168.12.0/30 is subnetted, 4 subnets
C 192.168.12.4 is directly connected, Serial0/1
C 192.168.12.0 is directly connected, Serial0/0
O 192.168.12.12 [110/74] via 192.168.12.10, 00:13:51, Serial0/2
[110/74] via 192.168.12.6, 00:13:51, Serial0/1
[110/74] via 192.168.12.2, 00:13:51, Serial0/0
C 192.168.12.8 is directly connected, Serial0/2
10.0.0.0/24 is subnetted, 2 subnets
C 10.12.12.0 is directly connected, Serial0/3
O 10.1.1.0 [110/128] via 10.12.12.1, 00:15:00, Serial0/3
192.168.1.0/30 is subnetted, 4 subnets
O IA 192.168.1.8 [110/192] via 10.12.12.1, 00:13:51, Serial0/3
O IA 192.168.1.12 [110/202] via 10.12.12.1, 00:13:51, Serial0/3
O IA 192.168.1.0 [110/192] via 10.12.12.1, 00:13:51, Serial0/3
O IA 192.168.1.4 [110/192] via 10.12.12.1, 00:13:51, Serial0/3

r5#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is 192.168.12.5 to network 0.0.0.0

192.168.12.0/30 is subnetted, 4 subnets
C 192.168.12.4 is directly connected, Serial0/1
C 192.168.12.0 is directly connected, Serial0/0
C 192.168.12.12 is directly connected, Ethernet1/1
O 192.168.12.8 [110/74] via 192.168.12.14, 00:14:09, Ethernet1/1
O*IA 0.0.0.0/0 [110/65] via 192.168.12.5, 00:14:09, Serial0/1
[110/65] via 192.168.12.1, 00:14:09, Serial0/0

r6#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is 192.168.12.9 to network 0.0.0.0

192.168.12.0/30 is subnetted, 4 subnets
O 192.168.12.4 [110/74] via 192.168.12.13, 00:14:17, Ethernet1/1
O 192.168.12.0 [110/74] via 192.168.12.13, 00:14:17, Ethernet1/1
C 192.168.12.12 is directly connected, Ethernet1/1
C 192.168.12.8 is directly connected, Serial0/2
O*IA 0.0.0.0/0 [110/65] via 192.168.12.9, 00:14:17, Serial0/2

r7#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

192.168.12.0/30 is subnetted, 4 subnets
O IA 192.168.12.4 [110/128] via 10.12.12.2, 00:17:43, Serial0/2
O IA 192.168.12.0 [110/128] via 10.12.12.2, 00:17:53, Serial0/2
O IA 192.168.12.12 [110/138] via 10.12.12.2, 00:14:59, Serial0/2
O IA 192.168.12.8 [110/128] via 10.12.12.2, 00:17:43, Serial0/2
10.0.0.0/24 is subnetted, 2 subnets
C 10.12.12.0 is directly connected, Serial0/2
C 10.1.1.0 is directly connected, Serial0/1
192.168.1.0/30 is subnetted, 4 subnets
O IA 192.168.1.8 [110/128] via 10.1.1.2, 00:17:53, Serial0/1
O IA 192.168.1.12 [110/138] via 10.1.1.2, 00:17:53, Serial0/1
O IA 192.168.1.0 [110/128] via 10.1.1.2, 00:17:53, Serial0/1
O IA 192.168.1.4 [110/128] via 10.1.1.2, 00:17:53, Serial0/1

r1#show ip ospf neighbor

Neighbor ID Pri State Dead Time Address Interface
7.7.7.7 0 FULL/ - 00:00:33 10.1.1.1 Serial0/3
3.3.3.3 0 FULL/ - 00:00:34 192.168.1.10 Serial0/2
2.2.2.2 0 FULL/ - 00:00:34 192.168.1.6 Serial0/1
2.2.2.2 0 FULL/ - 00:00:34 192.168.1.2 Serial0/0

r2#show ip ospf neighbor

Neighbor ID Pri State Dead Time Address Interface
3.3.3.3 1 FULL/DR 00:00:36 192.168.1.14 Ethernet1/1
1.1.1.1 0 FULL/ - 00:00:35 192.168.1.5 Serial0/1
1.1.1.1 0 FULL/ - 00:00:35 192.168.1.1 Serial0/0

r3#show ip ospf neighbor

Neighbor ID Pri State Dead Time Address Interface
2.2.2.2 1 FULL/BDR 00:00:36 192.168.1.13 Ethernet1/1
1.1.1.1 0 FULL/ - 00:00:35 192.168.1.9 Serial0/2

r4#show ip ospf neighbor

Neighbor ID Pri State Dead Time Address Interface
7.7.7.7 0 FULL/ - 00:00:32 10.12.12.1 Serial0/3
6.6.6.6 0 FULL/ - 00:00:37 192.168.12.10 Serial0/2
5.5.5.5 0 FULL/ - 00:00:39 192.168.12.6 Serial0/1
5.5.5.5 0 FULL/ - 00:00:39 192.168.12.2 Serial0/0

r5#show ip ospf neighbor

Neighbor ID Pri State Dead Time Address Interface
6.6.6.6 1 FULL/DR 00:00:36 192.168.12.14 Ethernet1/1
4.4.4.4 0 FULL/ - 00:00:31 192.168.12.5 Serial0/1
4.4.4.4 0 FULL/ - 00:00:34 192.168.12.1 Serial0/0

r6#show ip ospf neighbor

Neighbor ID Pri State Dead Time Address Interface
5.5.5.5 1 FULL/BDR 00:00:31 192.168.12.13 Ethernet1/1
4.4.4.4 0 FULL/ - 00:00:31 192.168.12.9 Serial0/2

r7#show ip ospf neighbor

Neighbor ID Pri State Dead Time Address Interface
4.4.4.4 0 FULL/ - 00:00:33 10.12.12.2 Serial0/2
1.1.1.1 0 FULL/ - 00:00:37 10.1.1.2 Serial0/1

任务7.修改AREA 12的完全末节区域为标准区域，配置环回接口。

r4(config)#router ospf 10

r4(config-router)#no area 12 stub no-summary
r4(config-router)#no area 12 stub
r4(config-router)#end

r5(config)#router ospf 10
r5(config-router)#no area 12 stub
r5(config-router)#end

r6(config)#router ospf 10
r6(config-router)#no area 12 stub
r6(config-router)#end
r6(config)#int lo0
r6(config-if)#ip add 172.16.12.1 255.255.255.252
r6(config-if)#no shut
r6(config-if)#end

任务8.发布OSPF AS外部直连环回接口到OSPF AS中，并配置ROUTER 6的缺省路由，并测试ROUTER 7与ROUTER 6的环回连通性【截图验证】。

r6(config)#router ospf 10
r6(config-router)#redistribute connected subnets
r6(config-router)#end

r5#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

192.168.12.0/30 is subnetted, 4 subnets
C 192.168.12.4 is directly connected, Serial0/1
C 192.168.12.0 is directly connected, Serial0/0
C 192.168.12.12 is directly connected, Ethernet1/1
O 192.168.12.8 [110/74] via 192.168.12.14, 00:00:06, Ethernet1/1
172.16.0.0/30 is subnetted, 1 subnets
O E2 172.16.12.0 [110/20] via 192.168.12.14, 00:00:06, Ethernet1/1
10.0.0.0/24 is subnetted, 2 subnets
O IA 10.12.12.0 [110/128] via 192.168.12.5, 00:00:06, Serial0/1
[110/128] via 192.168.12.1, 00:00:06, Serial0/0
O IA 10.1.1.0 [110/192] via 192.168.12.5, 00:00:06, Serial0/1
[110/192] via 192.168.12.1, 00:00:06, Serial0/0
192.168.1.0/30 is subnetted, 4 subnets
O IA 192.168.1.8 [110/256] via 192.168.12.5, 00:12:15, Serial0/1
[110/256] via 192.168.12.1, 00:12:15, Serial0/0
O IA 192.168.1.12 [110/266] via 192.168.12.5, 00:12:16, Serial0/1
[110/266] via 192.168.12.1, 00:12:16, Serial0/0
O IA 192.168.1.0 [110/256] via 192.168.12.5, 00:12:16, Serial0/1
[110/256] via 192.168.12.1, 00:12:16, Serial0/0
O IA 192.168.1.4 [110/256] via 192.168.12.5, 00:12:20, Serial0/1
[110/256] via 192.168.12.1, 00:12:20, Serial0/0

r7#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

192.168.12.0/30 is subnetted, 4 subnets
O IA 192.168.12.4 [110/128] via 10.12.12.2, 00:40:46, Serial0/2
O IA 192.168.12.0 [110/128] via 10.12.12.2, 00:40:46, Serial0/2
O IA 192.168.12.12 [110/138] via 10.12.12.2, 00:26:56, Serial0/2
O IA 192.168.12.8 [110/128] via 10.12.12.2, 00:40:46, Serial0/2
172.16.0.0/30 is subnetted, 1 subnets
O E2 172.16.12.0 [110/20] via 10.12.12.2, 00:12:04, Serial0/2
10.0.0.0/24 is subnetted, 2 subnets
C 10.12.12.0 is directly connected, Serial0/2
C 10.1.1.0 is directly connected, Serial0/1
192.168.1.0/30 is subnetted, 4 subnets
O IA 192.168.1.8 [110/128] via 10.1.1.2, 00:40:46, Serial0/1
O IA 192.168.1.12 [110/138] via 10.1.1.2, 00:40:46, Serial0/1
O IA 192.168.1.0 [110/128] via 10.1.1.2, 00:40:47, Serial0/1
O IA 192.168.1.4 [110/128] via 10.1.1.2, 00:40:47, Serial0/1

r7#ping 172.16.12.1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.12.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 52/87/116 ms

r1#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

192.168.12.0/30 is subnetted, 4 subnets
O IA 192.168.12.4 [110/192] via 10.1.1.1, 00:44:34, Serial0/3
O IA 192.168.12.0 [110/192] via 10.1.1.1, 00:44:34, Serial0/3
O IA 192.168.12.12 [110/202] via 10.1.1.1, 00:30:54, Serial0/3
O IA 192.168.12.8 [110/192] via 10.1.1.1, 00:44:34, Serial0/3
172.16.0.0/30 is subnetted, 1 subnets
O E2 172.16.12.0 [110/20] via 10.1.1.1, 00:16:02, Serial0/3
10.0.0.0/24 is subnetted, 2 subnets
O 10.12.12.0 [110/128] via 10.1.1.1, 00:44:49, Serial0/3
C 10.1.1.0 is directly connected, Serial0/3
192.168.1.0/30 is subnetted, 4 subnets
C 192.168.1.8 is directly connected, Serial0/2
O 192.168.1.12 [110/74] via 192.168.1.10, 00:44:34, Serial0/2
[110/74] via 192.168.1.6, 00:44:34, Serial0/1
[110/74] via 192.168.1.2, 00:44:34, Serial0/0
C 192.168.1.0 is directly connected, Serial0/0
C 192.168.1.4 is directly connected, Serial0/1

任务9.观察路由表，观察BORD-ROUTER表【截图验证】。

r1#show ip route

Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

192.168.12.0/30 is subnetted, 4 subnets
O IA 192.168.12.4 [110/192] via 10.1.1.1, 00:49:18, Serial0/3
O IA 192.168.12.0 [110/192] via 10.1.1.1, 00:49:18, Serial0/3
O IA 192.168.12.12 [110/202] via 10.1.1.1, 00:35:39, Serial0/3
O IA 192.168.12.8 [110/192] via 10.1.1.1, 00:49:18, Serial0/3
172.16.0.0/30 is subnetted, 1 subnets
O E2 172.16.12.0 [110/20] via 10.1.1.1, 00:20:47, Serial0/3
10.0.0.0/24 is subnetted, 2 subnets
O 10.12.12.0 [110/128] via 10.1.1.1, 00:49:34, Serial0/3
C 10.1.1.0 is directly connected, Serial0/3
192.168.1.0/30 is subnetted, 4 subnets
C 192.168.1.8 is directly connected, Serial0/2
O 192.168.1.12 [110/74] via 192.168.1.10, 00:49:18, Serial0/2
[110/74] via 192.168.1.6, 00:49:18, Serial0/1
[110/74] via 192.168.1.2, 00:49:19, Serial0/0
C 192.168.1.0 is directly connected, Serial0/0
C 192.168.1.4 is directly connected, Serial0/1

r1#show ip ospf border-routers

OSPF Process 10 internal Routing Table

Codes: i - Intra-area route, I - Inter-area route

i 4.4.4.4 [128] via 10.1.1.1, Serial0/3, ABR, Area 0, SPF 6
I 6.6.6.6 [192] via 10.1.1.1, Serial0/3, ASBR, Area 0, SPF 6

r2#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is 192.168.1.5 to network 0.0.0.0

192.168.12.0/30 is subnetted, 4 subnets
O IA 192.168.12.4 [110/256] via 192.168.1.5, 00:49:44, Serial0/1
[110/256] via 192.168.1.1, 00:49:44, Serial0/0

O IA 192.168.12.0 [110/256] via 192.168.1.5, 00:49:44, Serial0/1
[110/256] via 192.168.1.1, 00:49:44, Serial0/0
O IA 192.168.12.12 [110/266] via 192.168.1.5, 00:35:59, Serial0/1
[110/266] via 192.168.1.1, 00:35:59, Serial0/0
O IA 192.168.12.8 [110/256] via 192.168.1.5, 00:49:44, Serial0/1
[110/256] via 192.168.1.1, 00:49:44, Serial0/0
10.0.0.0/24 is subnetted, 2 subnets
O IA 10.12.12.0 [110/192] via 192.168.1.5, 00:49:44, Serial0/1
[110/192] via 192.168.1.1, 00:49:44, Serial0/0
O IA 10.1.1.0 [110/128] via 192.168.1.5, 00:49:44, Serial0/1
[110/128] via 192.168.1.1, 00:49:44, Serial0/0
192.168.1.0/30 is subnetted, 4 subnets
O 192.168.1.8 [110/74] via 192.168.1.14, 00:49:45, Ethernet1/1
C 192.168.1.12 is directly connected, Ethernet1/1
C 192.168.1.0 is directly connected, Serial0/0
C 192.168.1.4 is directly connected, Serial0/1
O*IA 0.0.0.0/0 [110/65] via 192.168.1.5, 00:49:45, Serial0/1
[110/65] via 192.168.1.1, 00:49:45, Serial0/0

r2#show ip ospf border-routers

OSPF Process 10 internal Routing Table

Codes: i - Intra-area route, I - Inter-area route

i 1.1.1.1 [64] via 192.168.1.5, Serial0/1, ABR, Area 1, SPF 7
i 1.1.1.1 [64] via 192.168.1.1, Serial0/0, ABR, Area 1, SPF 7

r3#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is 192.168.1.9 to network 0.0.0.0

192.168.12.0/30 is subnetted, 4 subnets
O IA 192.168.12.4 [110/256] via 192.168.1.9, 00:49:57, Serial0/2
O IA 192.168.12.0 [110/256] via 192.168.1.9, 00:49:57, Serial0/2
O IA 192.168.12.12 [110/266] via 192.168.1.9, 00:36:13, Serial0/2
O IA 192.168.12.8 [110/256] via 192.168.1.9, 00:49:57, Serial0/2
10.0.0.0/24 is subnetted, 2 subnets
O IA 10.12.12.0 [110/192] via 192.168.1.9, 00:49:57, Serial0/2
O IA 10.1.1.0 [110/128] via 192.168.1.9, 00:49:57, Serial0/2
192.168.1.0/30 is subnetted, 4 subnets
C 192.168.1.8 is directly connected, Serial0/2
C 192.168.1.12 is directly connected, Ethernet1/1
O 192.168.1.0 [110/74] via 192.168.1.13, 00:49:58, Ethernet1/1
O 192.168.1.4 [110/74] via 192.168.1.13, 00:49:57, Ethernet1/1
O*IA 0.0.0.0/0 [110/65] via 192.168.1.9, 00:49:58, Serial0/2

r3#show ip ospf border-routers

OSPF Process 10 internal Routing Table

Codes: i - Intra-area route, I - Inter-area route

i 1.1.1.1 [64] via 192.168.1.9, Serial0/2, ABR, Area 1, SPF 5

r4#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is not set
192.168.12.0/30 is subnetted, 4 subnets
C 192.168.12.4 is directly connected, Serial0/1
C 192.168.12.0 is directly connected, Serial0/0
O 192.168.12.12 [110/74] via 192.168.12.10, 00:21:40, Serial0/2
[110/74] via 192.168.12.6, 00:21:40, Serial0/1
[110/74] via 192.168.12.2, 00:21:40, Serial0/0
C 192.168.12.8 is directly connected, Serial0/2
172.16.0.0/30 is subnetted, 1 subnets
O E2 172.16.12.0 [110/20] via 192.168.12.10, 00:21:40, Serial0/2
10.0.0.0/24 is subnetted, 2 subnets
C 10.12.12.0 is directly connected, Serial0/3
O 10.1.1.0 [110/128] via 10.12.12.1, 00:36:59, Serial0/3
192.168.1.0/30 is subnetted, 4 subnets
O IA 192.168.1.8 [110/192] via 10.12.12.1, 00:21:41, Serial0/3
O IA 192.168.1.12 [110/202] via 10.12.12.1, 00:21:41, Serial0/3
O IA 192.168.1.0 [110/192] via 10.12.12.1, 00:21:41, Serial0/3
O IA 192.168.1.4 [110/192] via 10.12.12.1, 00:21:41, Serial0/3

r4#show ip ospf border-routers

OSPF Process 10 internal Routing Table

Codes: i - Intra-area route, I - Inter-area route

i 1.1.1.1 [128] via 10.12.12.1, Serial0/3, ABR, Area 0, SPF 7
i 6.6.6.6 [64] via 192.168.12.10, Serial0/2, ASBR, Area 12, SPF 12

r5#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

192.168.12.0/30 is subnetted, 4 subnets
C 192.168.12.4 is directly connected, Serial0/1
C 192.168.12.0 is directly connected, Serial0/0
C 192.168.12.12 is directly connected, Ethernet1/1
O 192.168.12.8 [110/74] via 192.168.12.14, 00:21:54, Ethernet1/1
172.16.0.0/30 is subnetted, 1 subnets
O E2 172.16.12.0 [110/20] via 192.168.12.14, 00:21:54, Ethernet1/1
10.0.0.0/24 is subnetted, 2 subnets
O IA 10.12.12.0 [110/128] via 192.168.12.5, 00:21:54, Serial0/1
[110/128] via 192.168.12.1, 00:21:54, Serial0/0
O IA 10.1.1.0 [110/192] via 192.168.12.5, 00:21:54, Serial0/1
[110/192] via 192.168.12.1, 00:21:54, Serial0/0
192.168.1.0/30 is subnetted, 4 subnets
O IA 192.168.1.8 [110/256] via 192.168.12.5, 00:21:54, Serial0/1
[110/256] via 192.168.12.1, 00:21:54, Serial0/0
O IA 192.168.1.12 [110/266] via 192.168.12.5, 00:21:55, Serial0/1
[110/266] via 192.168.12.1, 00:21:55, Serial0/0
O IA 192.168.1.0 [110/256] via 192.168.12.5, 00:21:55, Serial0/1
[110/256] via 192.168.12.1, 00:21:55, Serial0/0
O IA 192.168.1.4 [110/256] via 192.168.12.5, 00:21:56, Serial0/1
[110/256] via 192.168.12.1, 00:21:56, Serial0/0

r5#show ip ospf border-routers

OSPF Process 10 internal Routing Table

Codes: i - Intra-area route, I - Inter-area route

i 4.4.4.4 [64] via 192.168.12.5, Serial0/1, ABR, Area 12, SPF 10
i 4.4.4.4 [64] via 192.168.12.1, Serial0/0, ABR, Area 12, SPF 10
i 6.6.6.6 [10] via 192.168.12.14, Ethernet1/1, ASBR, Area 12, SPF 10

r6#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

192.168.12.0/30 is subnetted, 4 subnets
O 192.168.12.4 [110/74] via 192.168.12.13, 00:22:09, Ethernet1/1
O 192.168.12.0 [110/74] via 192.168.12.13, 00:22:09, Ethernet1/1
C 192.168.12.12 is directly connected, Ethernet1/1
C 192.168.12.8 is directly connected, Serial0/2
172.16.0.0/30 is subnetted, 1 subnets
C 172.16.12.0 is directly connected, Loopback0
10.0.0.0/24 is subnetted, 2 subnets
O IA 10.12.12.0 [110/128] via 192.168.12.9, 00:22:09, Serial0/2
O IA 10.1.1.0 [110/192] via 192.168.12.9, 00:22:09, Serial0/2
192.168.1.0/30 is subnetted, 4 subnets
O IA 192.168.1.8 [110/256] via 192.168.12.9, 00:22:09, Serial0/2
O IA 192.168.1.12 [110/266] via 192.168.12.9, 00:22:09, Serial0/2
O IA 192.168.1.0 [110/256] via 192.168.12.9, 00:22:10, Serial0/2
O IA 192.168.1.4 [110/256] via 192.168.12.9, 00:22:10, Serial0/2

r6#show ip ospf border-routers

OSPF Process 10 internal Routing Table

Codes: i - Intra-area route, I - Inter-area route

i 4.4.4.4 [64] via 192.168.12.9, Serial0/2, ABR, Area 12, SPF 8

r7#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

192.168.12.0/30 is subnetted, 4 subnets
O IA 192.168.12.4 [110/128] via 10.12.12.2, 00:50:58, Serial0/2
O IA 192.168.12.0 [110/128] via 10.12.12.2, 00:50:58, Serial0/2
O IA 192.168.12.12 [110/138] via 10.12.12.2, 00:37:08, Serial0/2
O IA 192.168.12.8 [110/128] via 10.12.12.2, 00:50:58, Serial0/2
172.16.0.0/30 is subnetted, 1 subnets
O E2 172.16.12.0 [110/20] via 10.12.12.2, 00:22:16, Serial0/2
10.0.0.0/24 is subnetted, 2 subnets
C 10.12.12.0 is directly connected, Serial0/2
C 10.1.1.0 is directly connected, Serial0/1
192.168.1.0/30 is subnetted, 4 subnets
O IA 192.168.1.8 [110/128] via 10.1.1.2, 00:50:58, Serial0/1
O IA 192.168.1.12 [110/138] via 10.1.1.2, 00:50:58, Serial0/1
O IA 192.168.1.0 [110/128] via 10.1.1.2, 00:50:58, Serial0/1
O IA 192.168.1.4 [110/128] via 10.1.1.2, 00:50:59, Serial0/1

r7#show ip ospf border-routers

OSPF Process 10 internal Routing Table

Codes: i - Intra-area route, I - Inter-area route

i 4.4.4.4 [64] via 10.12.12.2, Serial0/2, ABR, Area 0, SPF 2
i 1.1.1.1 [64] via 10.1.1.2, Serial0/1, ABR, Area 0, SPF 2
I 6.6.6.6 [128] via 10.12.12.2, Serial0/2, ASBR, Area 0, SPF 2