这个 配置将验证一个OSPF虚电路(Virtual-Link)的过程,重点在观察虚链路连接的临时网络与正常区域间路由有何区别。上图中区域4(area 4)没有和area 0直接相连。在R2与R3之间 配置了一条虚链路。
// R1 //
int lo0
ip ad 1.1.1.1 255.255. 255.0
int e0
ip ad 192.1.1.1 255.255.255.0
router os 1
network 192.1.1.0 0.0.0.255 area 0
// R2 //
int lo0
ip ad 2.2.2.2 255.255.255.0
int e0
ip ad 192.1.1.2 255.255.255.0
int e1
ip ad 193.1.1.2 255.255.255.0
router os 1
network 192.1.1.0 0.0.0.255 area 0
network 193.1.1.0 0.0.0.255 area 1
// R3 //
int lo0
ip ad 3.3.3.3 255.255.255.0
int e1
ip ad 193.1.1.3 255.255.255.0
int e0
ip ad 194.1.1.3 255.255.255.0
router os 1
network 193.1.1.0 0.0.0.255 area 1
network 194.1.1.0 0.0.0.255 area 4
// R4 //
int lo0
ip ad 4.4.4.4 255.255.255.0
int e0
ip ad 194.1.1.4 255.255.255.0
router os 1
network 194.1.1.0 0.0.0.255 area 4
基本 配置完成后,我们在每台路由器上分别来验证一下:
r1#sh ip os nei
Neighbor ID Pri State Dead Time Address Interface
2.2.2.2 1 FULL/BDR 00:00:33 192.1.1.2 Ethernet0/0
r1#
r1#sh ip ro
1.0.0.0/24 is subnetted, 1 subnets
C 1.1.1.0 is directly connected, Loopback0
O IA 193.1.1.0/24 [110/20] via 192.1.1.2, 00:00:19, Ethernet0/0
C 192.1.1.0/24 is directly connected, Ethernet0/0
//注意R1上有关于193.1.1.0的路由条目,是属于IA类型(域间路由)
r2#sh ip os nei
Neighbor ID Pri State Dead Time Address Interface
1.1.1.1 1 FULL/DR 00:00:35 192.1.1.1 Ethernet0/0
3.3.3.3 1 FULL/BDR 00:00:35 193.1.1.3 Ethernet1/0
r2#
r2#
r2#sh ip ro
2.0.0.0/24 is subnetted, 1 subnets
C 2.2.2.0 is directly connected, Loopback0
C 193.1.1.0/24 is directly connected, Ethernet1/0
C 192.1.1.0/24 is directly connected, Ethernet0/0
r3#sh ip os nei
Neighbor ID Pri State Dead Time Address Interface
2.2.2.2 1 FULL/DR 00:00:32 193.1.1.2 Ethernet1/0
4.4.4.4 1 FULL/DR 00:00:34 194.1.1.4 Ethernet0/0
r3#sh ip ro
3.0.0.0/24 is subnetted, 1 subnets
C 3.3.3.0 is directly connected, Loopback0
C 193.1.1.0/24 is directly connected, Ethernet1/0
O IA 192.1.1.0/24 [110/20] via 193.1.1.2, 00:02:49, Ethernet1/0
C 194.1.1.0/24 is directly connected, Ethernet0/0
//注意R3中有关于192.1.1.0的路由是属于IA类型(域间路由)
r4#sh ip os nei
Neighbor ID Pri State Dead Time Address Interface
3.3.3.3 1 FULL/BDR 00:00:33 194.1.1.3 Ethernet0/0
r4#sh ip ro
4.0.0.0/24 is subnetted, 1 subnets
C 4.4.4.0 is directly connected, Loopback0
C 194.1.1.0/24 is directly connected, Ethernet0/0
//R4上没有关于AREA 0内的任何路由信息