解决OSPF Area0 被分割问题

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7layer 2007-03-05 09:31:14 博主文章分类：Cisco ©著作权

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解决方法也是采用虚链路

最初的配置

r1 配置

router>en
router#conf t
router(config)#host r1
r1(config)#ena sec 123
r1(config)#no ip domain-lookup
r1(config)#ban mot #Welcome to r1#
r1(config)#line vty 0 4
r1(config-line)#no login
r1(config-line)#line con 0
r1(config-line)#no exec-timeout
r1(config-if)#int lo0
r1(config-if)#ip add 1.1.1.1 255.255.255.255
r1(config-if)#int f 0/0
r1(config-if)#des link to r2
r1(config-if)#ip add 192.168.1.1 255.255.255.0
r1(config-if)#no shut
r1(config-if)#int f 1/0
r1(config-if)#des link to r3
r1(config-if)#ip add 192.168.2.1 255.255.255.0
r1(config-if)#no shut
r1(config-if)#router ospf 1
r1(config-router)#router-id 1.1.1.1
r1(config-router)#net 192.168.1.0 0.0.0.255 area 1
r1(config-router)#net 192.168.2.0 0.0.0.255 area 0
r1(config-router)#end
r1#

r2 配置

router>en
router#conf t
router(config)#host r2
r2(config)#ena sec 123
r2(config)#no ip domain-lookup
r2(config)#ban mot #Welcome to r2#
r2(config)#line vty 0 4
r2(config-line)#no login
r2(config-line)#line con 0
r2(config-line)#no exec-timeout
r2(config-if)#int lo0
r2(config-if)#des router-id
r2(config-if)#ip add 2.2.2.2 255.255.255.255
r2(config-if)#int f 0/0
r2(config-if)#des link to r1
r2(config-if)#ip add 192.168.1.2 255.255.255.0
r2(config-if)#no shut
r2(config-if)#int f 1/0
r2(config-if)#des link to r4
r2(config-if)#ip add 192.168.3.1 255.255.255.0
r2(config-if)#no shut
r2(config-if)#router ospf 1
r2(config-router)#router-id 2.2.2.2
r2(config-router)#net 192.168.1.0 0.0.0.255 area 1
r2(config-router)#net 192.168.3.0 0.0.0.255 area 0
r2(config-router)#end
r2#

r3 配置

router>en
router#conf t
router(config)#host r3
r3(config)#ena sec 123
r3(config)#no ip domain-lookup
r3(config)#ban mot #Welcome to r3#
r3(config)#line vty 0 4
r3(config-line)#no login
r3(config-line)#line con 0
r3(config-line)#no exec-timeout
r3(config-if)#int lo0
r3(config-if)#ip add 3.3.3.3 255.255.255.255
r3(config-if)#des router-id
r3(config-if)#int f 0/0
r3(config-if)#des link to r1
r3(config-if)#ip add 192.168.2.2 255.255.255.0
r3(config-if)#no shut
r3(config-if)#int f 1/0
r3(config-if)#des link to r5
r3(config-if)#ip add 192.168.4.1 255.255.255.0
r3(config-if)#no shut
r3(config-if)#router ospf 1
r3(config-router)#router-id 3.3.3.3
r3(config-router)#net 192.168.2.0 0.0.0.255 area 0
r3(config-router)#net 192.168.4.0 0.0.0.255 area 2
r3(config-router)#end
r3#

r4 配置

router>en
router#conf t
router(config)#host r4
r4(config)#ena sec 123
r4(config)#no ip domain-lookup
r4(config)#ban mot #Welcome to r4#
r4(config)#line vty 0 4
r4(config-line)#no login
r4(config-line)#line con 0
r4(config-line)#no exec-timeout
r4(config-if)#int lo0
r4(config-if)#des router-id
r4(config-if)#ip add 4.4.4.4 255.255.255.255
r4(config-if)#int f 0/0
r4(config-if)#des link to r2
r4(config-if)#ip add 192.168.3.2 255.255.255.0
r4(config-if)#no shut
r4(config-if)#int f 1/0
r4(config-if)#des link to r6
r4(config-if)#ip add 192.168.5.1 255.255.255.0
r4(config-if)#no shut
r4(config-if)#router ospf 1
r4(config-router)#router-id 4.4.4.4
r4(config-router)#net 192.168.3.0 0.0.0.255 area 0
r4(config-router)#net 192.168.5.0 0.0.0.255 area 3
r4(config-router)#end
r4#

r5 配置

router>en
router#conf t
router(config)#host r5
r5(config)#ena sec 123
r5(config)#no ip domain-lookup
r5(config)#ban mot #Welcome to r5#
r5(config)#line vty 0 4
r5(config-line)#no login
r5(config-line)#line con 0
r5(config-line)#no exec-timeout
r5(config-if)#int lo0
r5(config-if)#des router-id
r5(config-if)#ip add 5.5.5.5 255.255.255.255
r5(config-if)#int f 0/0
r5(config-if)#des link to r3
r5(config-if)#ip add 192.168.4.2 255.255.255.0
r5(config-if)#no shut
r5(config-if)#router ospf 1
r5(config-router)#router-id 5.5.5.5
r5(config-router)#net 192.168.4.0 0.0.0.255 area 2
r5(config-router)#end
r5#

r6 配置

router>en
router#conf t
router(config)#host r6
r6(config)#ena sec 123
r6(config)#no ip domain-lookup
r6(config)#ban mot #Welcome to r6#
r6(config)#line vty 0 4
r6(config-line)#no login
r6(config-line)#line con 0
r6(config-line)#no exec-timeout
r6(config-if)#int lo0
r6(config-if)#des router-id
r6(config-if)#ip add 6.6.6.6 255.255.255.255
r6(config-if)#int f 0/0
r6(config-if)#des link to r4
r6(config-if)#ip add 192.168.5.2 255.255.255.0
r6(config-if)#no shut
r6(config-if)#router ospf 1
r6(config-router)#router-id 6.6.6.6
r6(config-router)#net 192.168.5.0 0.0.0.255 area 3
r6(config-router)#end
r6#

断开 Area 0 时的 r1 跟 r2 路由表，只有自己这边的路由信息

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

     1.0.0.0/24 is subnetted, 1 subnets
C       1.1.1.0 is directly connected, Loopback0
O IA 192.168.4.0/24 [110/2] via 192.168.2.2, 00:03:55, FastEthernet1/0
C    192.168.1.0/24 is directly connected, FastEthernet0/0
C    192.168.2.0/24 is directly connected, FastEthernet1/0

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 not set

     2.0.0.0/32 is subnetted, 1 subnets
C       2.2.2.2 is directly connected, Loopback0
     192.168.5.0/32 is subnetted, 1 subnets
O IA    192.168.5.1 [110/2] via 192.168.3.2, 00:01:03, FastEthernet1/0
C    192.168.1.0/24 is directly connected, FastEthernet0/0
C    192.168.3.0/24 is directly connected, FastEthernet1/0

r1 与 r2 之间建立虚链路，将area0连接起来。

新的配置

r1 配置

r1(config-router)#area 1 virtual-link 2.2.2.2
r1(config-router)#end
r1#

r2 配置

r2(config-router)#area 1 virtual-link 1.1.1.1
r2(config-router)#end
r2#

area 0 合并后的路由表

Gateway of last resort is not set

     1.0.0.0/24 is subnetted, 1 subnets
C       1.1.1.0 is directly connected, Loopback0
O IA 192.168.4.0/24 [110/2] via 192.168.2.2, 00:00:00, FastEthernet1/0
     192.168.5.0/32 is subnetted, 1 subnets
O IA    192.168.5.1 [110/3] via 192.168.1.2, 00:00:00, FastEthernet0/0
C    192.168.1.0/24 is directly connected, FastEthernet0/0
C    192.168.2.0/24 is directly connected, FastEthernet1/0
O    192.168.3.0/24 [110/2] via 192.168.1.2, 00:00:00, FastEthernet0/0

Gateway of last resort is not set

     2.0.0.0/32 is subnetted, 1 subnets
C       2.2.2.2 is directly connected, Loopback0
O IA 192.168.4.0/24 [110/3] via 192.168.1.1, 00:00:24, FastEthernet0/0
     192.168.5.0/32 is subnetted, 1 subnets
O IA    192.168.5.1 [110/2] via 192.168.3.2, 00:00:24, FastEthernet1/0
C    192.168.1.0/24 is directly connected, FastEthernet0/0
O    192.168.2.0/24 [110/2] via 192.168.1.1, 00:00:24, FastEthernet0/0
C    192.168.3.0/24 is directly connected, FastEthernet1/0