自制OSPF配置实验大全
OSPF综合实验（gns模拟器）
注意点：
Ospf实验推荐用gns制作
//图中的交换机可以视觉忽略或缩小成一个点。（^
v^）
Ospf
实验拓扑图
目录
OSPF综合实验... 1
Ospf实验拓扑图... 1
1.Ospf 基础配置... 1
2.环回口改成点到点网络... 2
3.改优先级... 2
4.ospf的手动汇总... 2
5.ospf认证... 2
6.ospf发布缺省路由更新... 2
7.孤岛区域和区域分割... 2
8.STUB 和
NSSA的配置... 2
1.Ospf
基础配置
R1：
R1#conf t
R1(config)#inte0/0
R1(config-if)#ipadd 14.14.14.1 255.255.255.0
R1(config-if)#noshut
R1(config-if)#intlo0
R1(config-if)#ipadd 10.1.1.1 255.255.255.0
R1(config-if)#end
R1#conf t
R1(config)#routerospf 1
R1(config-router)#router-id1.1.1.1
R1(config-router)#net10.1.1.0 0.0.0.255 a 1
R1(config-router)#net14.14.14.0 0.0.0.255 a 1
R2：
R2#conf t
R2(config)#inte0/1
R2(config-if)#ipadd 123.123.123.2
255.255.255.0
R2(config-if)#noshut
R2(config-if)#intlo0
R2(config-if)#ipadd 20.2.2.2 255.255.255.0
R2(config-if)#noshut
R2(config-if)#end
R2#conf t
R2(config)#routerospf 1
R2(config-router)#router-id2.2.2.2
R2(config-router)#net123.123.123.2 0.0.0.0 a
0
R2(config-router)#net20.2.2.2 0.0.0.0 a 0
R2(config-router)#end
R3：
R3#conf t
R3(config)#inte0/1
R3(config-if)#ipadd 123.123.123.3 255.255.255.0
R3(config-if)#noshut
R3(config-if)#exit
R3(config)#routerospf 1
R3(config-router)#router-id3.3.3.3
R3(config-router)#net123.123.123.3 0.0.0.0 a 0
R3(config-router)#end
R4：
R4#conf t
R4(config)#inte0/0
R4(config-if)#ipadd 14.14.14.4 255.255.255.0
R4(config-if)#noshut
R4(config-if)#inte0/1
R4(config-if)#ipadd 123.123.123.4 255.255.255.0
R4(config-if)#noshut
R4(config)#intlo0
R4(config-if)#ipadd 90.9.9.9 255.255.255.0
R4(config-if)#end
R4#conf t
R4(config)#routerospf 1
R4(config-router)#router
R4(config-router)#router-id4.4.4.4
R4(config-router)#net14.14.14.0 0.0.0.255 a 1
R4(config-router)#net123.123.123.4 0.0.0.0 a 0
R4(config-router)#end
R5：
R5#conf t
R5(config)#inte0/0
R5(config-if)#ipadd 56.56.56.5 255.255.255.0
R5(config-if)#noshut
R5(config-if)#inte0/1
R5(config-if)#ipadd 123.123.123.5 255.255.255.0
R5(config-if)#noshut
R5(config-if)#end
R5#conf t
R5(config)#routerospf 1
R5(config-router)#router-id5.5.5.5
R5(config-router)#net123.123.123.5 0.0.0.0 a 0
R5(config-router)#net56.56.56.0 0.0.0.255 a 2
R5(config-router)#end
R6：
R6#conf t
R6(config)#inte0/0
R6(config-if)#ipadd 56.56.56.6 255.255.255.0
R6(config-if)#noshut
R6(config-if)#inte0/1
R6(config-if)#ipadd 67.67.67.6 255.255.255.0
R6(config-if)#noshut
R6(config-if)#intlo0
R6(config-if)#ipadd 60.6.6.6 255.255.255.0
R6(config-if)#end
R6#conf t
R6(config)#routerospf 1
R6(config-router)#router-id6.6.6.6
R6(config-router)#net60.6.6.0 0.0.0.255 a 2
R6(config-router)#net56.56.56.0 0.0.0.255 a 2
R6(config-router)#net67.67.67.0 0.0.0.255 a 3
R6(config-router)#end
R7：
R7#conf t
R7(config)#inte0/1
R7(config-if)#ipadd 67.67.67.7 255.255.255.0
R7(config-if)#noshut
R7(config-if)#intlo 0
R7(config-if)#ipadd 70.7.7.7 255.255.255.0
R1(config-if)#intlo 1
R1(config-if)#ipadd 80.8.8.8 255.255.255.0
R7(config-if)#end
R7#conf t
R7(config)#routerospf 1
R7(config-router)#router-id7.7.7.7
R7(config-router)#net70.7.7.0 0.0.0.255 a 3
R7(config-router)#net67.67.67.0 0.0.0.255 a 3
R7(config-router)#end
检验邻居关系
R4#show ip ospf neighbor
NeighborID Pri State Dead
Time Address Interface
2.2.2.2 1 FULL/DROTHER 00:00:30 123.123.123.2 Ethernet0/1
3.3.3.3 1 FULL/DROTHER 00:00:35 123.123.123.3 Ethernet0/1
5.5.5.5 1 FULL/DR 00:00:34 123.123.123.5 Ethernet0/1
1.1.1.1 1 FULL/BDR 00:00:35 14.14.14.1 Ethernet0/0
R4#show ip routeospf
20.0.0.0/32is
subnetted, 1 subnets
O 20.2.2.2[110/11]
via 123.123.123.2, 00:33:28, Ethernet0/1
10.0.0.0/32
issubnetted, 1 subnets
O 10.1.1.1
[110/11]via 14.14.14.1, 00:33:28, Ethernet0/0
56.0.0.0/24
is subnetted, 1 subnets
O
IA 56.56.56.0
[110/20] via 123.123.123.5,00:33:28, Ethernet0/1
60.0.0.0/32
is subnetted, 1 subnets
O
IA 60.6.6.6
[110/21] via 123.123.123.5,00:33:28, Ethernet0/1
2.
环回口改成点到点网络
由于环回口被视为主机，环回口网络总被当作主机路由学习
10.0.0.0/32 is subnetted, 1
subnets
O 10.1.1.1[110/11]
via 14.14.14.1, 00:33:28, Ethernet0/0
现在将R1 环回口0 改成点到点网络
R1#show ip ospf interface loopback 0
Loopback0is up, line protocol is up
Internet
Address 10.1.1.1/24,Area 1
Process
ID 1, Router ID 1.1.1.1,Network Type LOOPBACK, Cost: 1
Loopbackinterface is treated as a stub Host
R1：
R1#CONF T
R1(config)#intlo 0
R1(config-if)#ipospf network point-to-point
检验：
R1#show ip ospf interface loopback 0
Loopback0is up, line protocol is up
Internet
Address 10.1.1.1/24,Area 1
Process
ID 1, Router ID 1.1.1.1,Network Type POINT_TO_POINT, Cost:
1
Transmit
Delay is 1 sec, StatePOINT_TO_POINT,
Timer
intervals configured, Hello 10, Dead40, Wait 40, Retransmit
5
oob-resync
timeout 40
Supports
Link-local Signaling (LLS)
Index
1/1, flood queue length 0
Next
0x0(0)/0x0(0)
Last
flood scan length is 0, maximum is 0
Last
flood scan time is 0 msec, maximum is 0msec
Neighbor
Count is 0, Adjacent neighbor countis 0
Suppresshello for 0 neighbor(s)
R4#show ip route ospf
20.0.0.0/32is
subnetted, 1 subnets
O 20.2.2.2[110/11]
via 123.123.123.2, 00:45:58, Ethernet0/1
10.0.0.0/24is
subnetted, 1 subnets
O 10.1.1.0[110/11]
via 14.14.14.1, 00:01:39, Ethernet0/0
56.0.0.0/24
is subnetted, 1 subnets
O
IA 56.56.56.0
[110/20] via 123.123.123.5,00:01:39, Ethernet0/1
60.0.0.0/32
is subnetted, 1 subnets
O
IA 60.6.6.6
[110/21] via 123.123.123.5,00:01:39, Ethernet0/1
3.
改优先级
由于ospf配置后，先配置的就变为DR,BDR。因此如果先配置R2，R3则R2，R3是DR,BDR
现在要将R5变成DR,R4变为BDR。那么就是将R2，R3，R4的优先级变为0，放弃DR,BDR竞选，然后再将其R4，R3，R2优先级恢复为1.
R2，R3，R4的优先级变为0，放弃DR,BDR竞选
R2:
R2(config)#INTE0/1
R2(config-if)#IPOSPF PRI
R2(config-if)#IPOSPF PRIority 0
R3:
R3#conf t
R3(config)#inte0/1
R3(config-if)#ipospf priority 0
R4:
R4#conf t
R4(config)#inte0/1
R4(config-if)#ipospf priority 0
R4，R3，R2优先级恢复为1.
R4:
R4#conf t
R4(config)#inte0/1
R4(config-if)#ipospf priority 1
R3:
R3#conf t
R3(config)#inte0/1
R3(config-if)#ipospf priority 1
R2:
R2#conf t
R2(config)#inte0/1
R2(config-if)#ipospf priority 1
检验：
R2#show ip ospf nei
NeighborID Pri State Dead
Time Address Interface
3.3.3.3 1 2WAY/DROTHER 00:00:37 123.123.123.3 Ethernet0/1
4.4.4.4 1 FULL/BDR 00:00:37 123.123.123.4 Ethernet0/1
5.5.5.5 1 FULL/DR 00:00:32 123.123.123.5 Ethernet0/1
4.ospf
的手动汇总
4.1)区域间手动汇总（只能在ABR上做）
R4#conf t
R4(config)#routerospf
1 //进入ospf
1
R4(config-router)#area1 range
10.0.0.0 255.0.0.0
验证：
R5#show ip route ospf
20.0.0.0/32is
subnetted, 1 subnets
O 20.2.2.2[110/11]
via 123.123.123.2, 01:22:01, Ethernet0/1
O IA 10.0.0.0/8 [110/21]via 123.123.123.4, 00:01:19,
Ethernet0/1
14.0.0.0/24is
subnetted, 1 subnets
O
IA 14.14.14.0[110/20]
via 123.123.123.4, 01:22:01, Ethernet0/1
60.0.0.0/32
is subnetted, 1 subnets
O 60.6.6.6
[110/11] via 56.56.56.6,01:22:01, Ethernet0/0
R6#show ip route ospf
70.0.0.0/32
is subnetted, 1 subnets
O 70.7.7.7
[110/11] via 67.67.67.7,01:23:44, Ethernet0/1
20.0.0.0/32is
subnetted, 1 subnets
O
IA 20.2.2.2
[110/21]via 56.56.56.5, 01:23:34, Ethernet0/0
O IA 10.0.0.0/8[110/31] via 56.56.56.5,
00:02:57, Ethernet0/0
123.0.0.0/24
is subnetted, 1 subnets
O
IA 123.123.123.0
[110/20] via 56.56.56.5,01:23:34, Ethernet0/0
14.0.0.0/24is
subnetted, 1 subnets
O
IA 14.14.14.0[110/30]
via 56.56.56.5, 01:23:34, Ethernet0/0
5.ospf
认证
链路认证：ABR 与常规
明文：
R1:
R1#conf t
R1(config)#inte0/0
R1(config-if)#ipospf
authentication //启用明文认证
R1(config-if)#ipospf authentication-key abc123
R4:
R4#conf t
R4(config)#inte0/0
R4(config-if)#ipospf authentication
R4(config-if)#ipospf authentication-key abc123
密文：
R6#conf t
R6(config)#inte0/0
R6(config-if)#ipospf authentication
message-digest
R6(config-if)#ipospf message-digest-key 1 md5
abc
R5#conf t
R5(config)#inte0/0
R5(config-if)#ipospf authentication
message-digest
R5(config-if)#ipospf message-digest-key 1 md5
abc
区域认证：骨干
密文：
R2#conf t
R2(config)#routerospf 1
R2(config-router)#area0 authentication
message-digest
R2(config-router)#exit
R2(config)#inte0/1
R2(config-if)#ipospf message-digest-key 2 md5
CHINA
R3#conf t
R3(config)#routerospf 1
R3(config-router)#area0 authentication
message-digest
R3(config-router)#ipospf message
R3(config-router)#exit
R3(config)#inte0/1
R3(config-if)#ipospf message-digest-key 2 md5
CHINA
R4#conf t
R4(config)#routerospf 1
R4(config-router)#area0 authentication
message-digest
R4(config-router)#exit
R4(config)#inte0/1
R4(config-if)#ipospf message-digest-key 2 md5
CHINA
R5#conf t
R5(config)#routerospf 1
R5(config-router)#area0 authentication
message-digest
R5(config-router)#exit
R5(config)#inte0/1
R5(config-if)#ipospf message-digest-key 2 md5
CHINA
区域所有设备接口参与，除环回口
6.ospf
发布缺省路由更新
R2#conf t
R2(config)#router ospf 1
R2(config-router)#default-informationoriginate always
metric 2
现象：
R5#showip route ospf
20.0.0.0/32
is subnetted, 1 subnets
O 20.2.2.2
[110/11] via 123.123.123.2,00:00:33, Ethernet0/1
O IA10.0.0.0/8 [110/21] via 123.123.123.4, 00:00:33,
Ethernet0/1
14.0.0.0/24
is subnetted, 1 subnets
O
IA 14.14.14.0
[110/20] via 123.123.123.4,00:00:33, Ethernet0/1
60.0.0.0/32
is subnetted, 1 subnets
O 60.6.6.6
[110/11] via 56.56.56.6,00:52:03, Ethernet0/0
O*E2 0.0.0.0/0 [110/2] via 123.123.123.2,
00:00:33,Ethernet0/1
7.
孤岛区域和区域分割
孤岛区域就是没有通过ABR和骨干区域相连的常规区域（图中的area
3）
解决方案：虚电路virtual-link
骨干区域做链路认证，虚电路必须启动认证
R6#conf t
R6(config)#routerospf 1
R6(config-router)#area2 virtual-link
5.5.5.5 //虚链路配置完成（没有认证的话）
R6(config-router)#AREA2 virtual-link 5.5.5.5
authentication
message-digest
R6(config-router)#area2 virtual-link 5.5.5.5
message-digest-key 2 md5 CHINA
R6(config-router)#end
R5#conf t
R5(config)#routerospf 1
R5(config-router)#area2 virtual-link 6.6.6.6
R5(config-router)#AREA2 virtual-link 6.6.6.6
authentication message-digest
R5(config-router)#area2 virtual-link 6.6.6.6
message-digest-key 2 md5 CHINA
R5(config-router)#end
测试：
1.R7#ping 10.1.1.1 so 70.7.7.7
2.
R6#showip ospf neighbor
NeighborID Pri State Dead
Time Address Interface
5.5.5.5 0 FULL/ - - 56.56.56.5 OSPF_VL1
5.5.5.5 1 FULL/BDR 00:00:34 56.56.56.5 Ethernet0/0
7.7.7.7 1 FULL/DR 00:00:35 67.67.67.7 Ethernet0/1
3.路由表对比
虚拟链路前：
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-ISlevel-2
ia
- IS-IS inter area, * - candidatedefault, U - per-user static
route
o
- ODR, P - periodic downloaded staticroute
Gatewayof last resort is not set
20.0.0.0/24
is subnetted, 1 subnets
C 20.2.2.0
is directly connected,Loopback0
O IA10.0.0.0/8 [110/21] via 123.123.123.4, 00:38:57,
Ethernet0/1
56.0.0.0/24
is subnetted, 1 subnets
O
IA 56.56.56.0
[110/20] via 123.123.123.5,00:38:57, Ethernet0/1
123.0.0.0/24
is subnetted, 1 subnets
C 123.123.123.0
is directly connected,Ethernet0/1
14.0.0.0/24
is subnetted, 1 subnets
O
IA 14.14.14.0
[110/20] via 123.123.123.4,00:38:57, Ethernet0/1
60.0.0.0/32
is subnetted, 1 subnets
O
IA 60.6.6.6
[110/21] via 123.123.123.5,00:38:59, Ethernet0/1
虚拟链路后：
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-ISlevel-2
ia
- IS-IS inter area, * - candidatedefault, U - per-user static
route
o
- ODR, P - periodic downloaded staticroute
Gatewayof last resort is not set
70.0.0.0/32
issubnetted, 1 subnets
O
IA 70.7.7.7[110/31]
via 123.123.123.5, 00:00:02, Ethernet0/1
20.0.0.0/24
is subnetted, 1 subnets
C 20.2.2.0
is directly connected,Loopback0
67.0.0.0/24
is subnetted, 1 subnets
O
IA 67.67.67.0[110/30]
via 123.123.123.5, 00:00:02, Ethernet0/1
O IA10.0.0.0/8 [110/21] via 123.123.123.4, 00:00:02,
Ethernet0/1
56.0.0.0/24
is subnetted, 1 subnets
O
IA 56.56.56.0
[110/20] via 123.123.123.5,00:00:02, Ethernet0/1
123.0.0.0/24
is subnetted, 1 subnets
C 123.123.123.0
is directly connected,Ethernet0/1
14.0.0.0/24
is subnetted, 1 subnets
O
IA 14.14.14.0
[110/20] via 123.123.123.4,00:00:04, Ethernet0/1
60.0.0.0/32
is subnetted, 1 subnets
O
IA 60.6.6.6
[110/21] via 123.123.123.5,00:05:40, Ethernet0/1
8.STUB
和
NSSA的配置
8.1）将外部路由嵌套入ospf
R7#conf t
R7(config)#routerrip
R7(config-router)#version2
R7(config-router)#noauto-summary
R7(config-router)#net80.8.8.0
R7(config-router)#exit
R7(config)#routerospf 1
R7(config-router)#redistributerip subnets
R7(config-router)#end
R4#conf t
R4(config)#routereigrp 1
R4(config-router)#noauto-summary
R4(config-router)#eigrp router-id 40.4.4.4
R4(config-router)#net90.9.9.0 0.0.0.255
R4(config-router)#exit
R4(config)#routerospf 1
R4(config-router)#redistributeeigrp 1 subnets
R4(config-router)#end
测试：
R2#show ip rout ospf
70.0.0.0/32
is subnetted, 1 subnets
O
IA 70.7.7.7
[110/31] via 123.123.123.5,00:06:45, Ethernet0/1
80.0.0.0/24
is subnetted, 1 subnets
O
E2 80.8.8.0
[110/20] via 123.123.123.5,00:00:39, Ethernet0/1
67.0.0.0/24
is subnetted, 1 subnets
O
IA 67.67.67.0
[110/30] via 123.123.123.5,00:06:45, Ethernet0/1
O IA10.0.0.0/8 [110/21] via 123.123.123.4, 00:06:45,
Ethernet0/1
56.0.0.0/24
is subnetted, 1 subnets
O
IA 56.56.56.0
[110/20] via 123.123.123.5,00:06:45, Ethernet0/1
14.0.0.0/24
is subnetted, 1 subnets
O
IA 14.14.14.0
[110/20] via 123.123.123.4,00:06:45, Ethernet0/1
90.0.0.0/24
is subnetted, 1 subnets
O
E2 90.9.9.0
[110/20] via 123.123.123.4,00:06:45, Ethernet0/1
60.0.0.0/32
is subnetted, 1 subnets
O
IA 60.6.6.6
[110/21] via 123.123.123.5,00:06:45, Ethernet0/1
8.2）T-STUB：
R4：
R4#conf t
R4(config)#routerospf 1
R4(config-router)#area1 stub no-summary
R1：
R1#conf t
R1(config)#routerospf 1
R1(config-router)#area1 stub
检验：
建立前：
R1#showip rou
ospf
70.0.0.0/32
is subnetted, 1 subnets
O
IA 70.7.7.7
[110/41] via 14.14.14.4, 00:10:18,Ethernet0/0
80.0.0.0/24
is subnetted, 1 subnets
O
E2 80.8.8.0
[110/20] via 14.14.14.4, 00:05:38,Ethernet0/0
20.0.0.0/32
is subnetted, 1 subnets
O
IA 20.2.2.2
[110/21] via 14.14.14.4, 00:10:18,Ethernet0/0
67.0.0.0/24
is subnetted, 1 subnets
O
IA 67.67.67.0
[110/40] via 14.14.14.4,00:10:18, Ethernet0/0
56.0.0.0/24
is subnetted, 1 subnets
O
IA 56.56.56.0
[110/30] via 14.14.14.4,00:10:18, Ethernet0/0
123.0.0.0/24
is subnetted, 1 subnets
O
IA 123.123.123.0
[110/20] via 14.14.14.4,00:10:18, Ethernet0/0
90.0.0.0/24
is subnetted, 1 subnets
O
E2 90.9.9.0
[110/20] via 14.14.14.4, 00:10:18,Ethernet0/0
60.0.0.0/32
is subnetted, 1 subnets
O
IA 60.6.6.6
[110/31] via 14.14.14.4, 00:10:18,Ethernet0/0
O*E2 0.0.0.0/0 [110/2] via 14.14.14.4,
00:10:18,Ethernet0/0
建立后：
R1#show ip route ospf
O*IA 0.0.0.0/0 [110/11] via 14.14.14.4,
00:00:34,Ethernet0/0
8.3)T-NSSA
R5#conf t
R5(config)#routerospf 1
R5(config-router)#area3 nssa no-summary
R7#conf t
R7(config)#routerospf 1
R7(config-router)#area2 nssa
R7(config-router)#end
————完——
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