实验十七、OSPF 在NBMA 网络的配置
一、 实验目的
1. 掌握OSPF 协议在NBMA （非广播多点可达）环境下的配置
2. 理解NBMA 环境的特殊性
二、 应用环境
在帧中继的网络中，通常一个物理接口对应多条PVC，DR 的选择非常重要，如在下图中，
要保证ROUTER-A 成为DR，才能保证OSPF 路由更新的正确
三、 实验设备
1. DCR-1751 三台
2. DCR-2630 （安装相应模块满足三个serial 接口） 一台
3. CR-V35FC 三条
4. CR-V35MT 三条
四、 实验拓扑
五、 实验要求
ROUTER-A ROUTER-B ROUTER-C
S1/1 192.168.1.1/24 S1/0 192.168.1.2/24 S03 192.168.1.3/24
F0/0 192.168.2.1/24 F0/0 192.168.3.1/24 F0/0 192.168.4.1/24六、 实验步骤
第一步：参照实验 15，将帧中继网络配置好，并测试连通性
第二步：配置路由器A、B、C 的OSPF 协议
Router-A#conf
Router-A_config#int f0/0
Router-A_config_f0/0#ip address 192.168.2.1 255.255.255.0
Router-A_config_f0/0#exit
Router-A_config#router ospf 1
Router-A_config_ospf_1#network 192.169.1.0 255.255.255.0 area 0
Router-A_config_ospf_1#network 192.169.2.0 255.255.255.0 area 0
Router-B#conf
Router-B_config#int f0/0
Router-B_config_f0/0#ip address 192.168.3.1 255.255.255.0
Router-B_config_f0/0#exit
Router-B_config#router ospf 1
Router-B_config_ospf_1#net 192.168.1.0 255.255.255.0 area 0
Router-B_config_ospf_1#net 192.168.3.0 255.255.255.0 area 0
Router-C#conf
Router-C_config#int f0/0
Router-C_config_f0/0#ip address 192.168.4.1 255.255.255.0
Router-C_config_rip#exit
Router-C_config#router ospf 1
Router-C_config_ospf_1#network 192.168.1.0 255.255.255.0 area 0
Router-C_config_ospf_1#network 192.168.4.0 255.255.255.0 area 0
第三步：查看各路由器的路由表
Router-A#sh ip route
Codes: C - connected, S - static, R - RIP, B - BGP, BC - BGP connected
D - DEIGRP, DEX - external DEIGRP, O - OSPF, OIA - OSPF inter area
ON1 - OSPF NSSA external type 1, ON2 - OSPF NSSA external type 2
OE1 - OSPF external type 1, OE2 - OSPF external type 2
DHCP - DHCP type
VRF ID: 0
C 192.168.2.0/24 is directly connected, FastEthernet0/0
C 192.168.1.0/24 is directly connected, Serial1/1
Router-B# sh ip route
Codes: C - connected, S - static, R - RIP, B - BGP, BC - BGP connected D - DEIGRP, DEX - external DEIGRP, O - OSPF, OIA - OSPF inter area
ON1 - OSPF NSSA external type 1, ON2 - OSPF NSSA external type 2
OE1 - OSPF external type 1, OE2 - OSPF external type 2
DHCP - DHCP type
VRF ID: 0
C 192.168.1.0/24 is directly connected, Serial1/0
C 192.168.3.0/24 is directly connected, FastEthernet0/0
Router-C#sh ip route
Codes: C - connected, S - static, R - RIP, B - BGP, BC - BGP connected
D - DEIGRP, DEX - external DEIGRP, O - OSPF, OIA - OSPF inter area
ON1 - OSPF NSSA external type 1, ON2 - OSPF NSSA external type 2
OE1 - OSPF external type 1, OE2 - OSPF external type 2
DHCP - DHCP type
VRF ID: 0
C 192.168.1.0/24 is directly connected, Serial0/3
C 192.168.4.0/24 is directly connected, FastEthernet0/0
!都没有得到OSPF 路由，说明在NBMA 环境下的需要做特定的配置
第四步：查看OSPF 状态
Router-A#sh ip ospf interface
Serial1/1 is up, line protocol is up
Internet Address: 192.168.1.1/24
Nettype: Non-Broadcast ！网络类型为非广播
OSPF process is 1, AREA: 0, Router ID: 192.168.1.1
Cost: 1600, Transmit Delay is 1 sec, Priority 1
Hello interval is 30, Dead timer is 120, Retransmit is 5
OSPF INTF State is IWAITING
Neighbor Count is 0, Adjacent neighbor count is 0
Router-B#sh ip ospf interface
Serial1/0 is up, line protocol is up
Internet Address: 192.168.1.2/24
Nettype: Non-Broadcast ！网络类型为非广播
OSPF process is 1, AREA: 0, Router ID: 192.168.2.1
Cost: 1600, Transmit Delay is 1 sec, Priority 1
Hello interval is 30, Dead timer is 120, Retransmit is 5
OSPF INTF State is IWAITING
Neighbor Count is 0, Adjacent neighbor count is 0 Router-C#sh ip ospf interface
Serial0/3 is up, line protocol is up
Internet Address: 192.168.1.3/24
Nettype: Non-Broadcast ！网络类型为非广播
OSPF process is 1, AREA: 0, Router ID: 192.168.4.1
Cost: 1600, Transmit Delay is 1 sec, Priority 1
Hello interval is 30, Dead timer is 120, Retransmit is 5
OSPF INTF State is IDrOTHER
Neighbor Count is 0, Adjacent neighbor count is 0
第五步：NBMA 环境下的配置
Router-A#conf
Router-A_config#router ospf 1
Router-A_config_ospf_1#neighbor 192.168.1.2 ！手工指定邻居
Router-A_config_ospf_1#neighbor 192.168.1.3
Router-B#conf
Router-B_config#int s1/0
Router-B_config_s1/0#ip ospf priority 0 ！使B 不参加DR 选举
Router-B_config_s1/0#exit
Router-B_config#router ospf 1
Router-B_config_ospf_1#neighbor 192.168.1.1 ！手工指定邻居
Router-C#conf
Router-C_config#int s0/3
Router-C_config_s0/3#ip ospf priority 0 ！使C 不参加DR 选举
Router-C_config_s0/3#exit
Router-C_config#router ospf 1
Router-C_config_ospf_1#neighbor 192.168.1.1 ！手工指定邻居
第六步：再次查看各路由表
Router-A#sh ip route
Codes: C - connected, S - static, R - RIP, B - BGP, BC - BGP connected
D - DEIGRP, DEX - external DEIGRP, O - OSPF, OIA - OSPF inter area
ON1 - OSPF NSSA external type 1, ON2 - OSPF NSSA external type 2
OE1 - OSPF external type 1, OE2 - OSPF external type 2
DHCP - DHCP type
VRF ID: 0
C 192.168.1.0/24 is directly connected, Serial1/1
C 192.168.2.0/24 is directly connected, FastEthernet0/0
O 192.168.3.0/24 [110,1601] via 192.168.1.2(on Serial1/1) O 192.168.4.0/24 [110,1601] via 192.168.1.3(on Serial1/1)
Router-B#sh ip route
Codes: C - connected, S - static, R - RIP, B - BGP, BC - BGP connected
D - DEIGRP, DEX - external DEIGRP, O - OSPF, OIA - OSPF inter area
ON1 - OSPF NSSA external type 1, ON2 - OSPF NSSA external type 2
OE1 - OSPF external type 1, OE2 - OSPF external type 2
DHCP - DHCP type
VRF ID: 0
C 192.168.1.0/24 is directly connected, Serial1/0
O 192.168.2.0/24 [110,1601] via 192.168.1.1(on Serial1/0)
C 192.168.3.0/24 is directly connected, FastEthernet0/0
O 192.168.4.0/24 [110,1601] via 192.168.1.3(on Serial1/0)
Router-C#sh ip route
Codes: C - connected, S - static, R - RIP, B - BGP, BC - BGP connected
D - DEIGRP, DEX - external DEIGRP, O - OSPF, OIA - OSPF inter area
ON1 - OSPF NSSA external type 1, ON2 - OSPF NSSA external type 2
OE1 - OSPF external type 1, OE2 - OSPF external type 2
DHCP - DHCP type
VRF ID: 0
C 192.168.1.0/24 is directly connected, Serial0/3
O 192.168.2.0/24 [110,1601] via 192.168.1.1(on Serial0/3)
O 192.168.3.0/24 [110,1601] via 192.168.1.2(on Serial0/3)
C 192.168.4.0/24 is directly connected, FastEthernet0/0
第七步：查看OSPF 状态
Router-A#sh ip ospf interface ！查看OSPF 接口状态
Serial1/1 is up, line protocol is up
Internet Address: 192.168.1.1/24
Nettype: Non-Broadcast
OSPF process is 1, AREA: 0, Router ID: 192.168.1.1
Cost: 1600, Transmit Delay is 1 sec, Priority 1
Hello interval is 30, Dead timer is 120, Retransmit is 5
OSPF INTF State is IDr
Designated Router ID: 192.168.1.1, Interface address 192.168.1.1 ！A 成为DR
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 192.168.2.1 ！OSPF 邻居
Adjacent with neighbor 192.168.4.1 FastEthernet0/0 is up, line protocol is up
Internet Address: 192.168.2.1/24
Nettype: Broadcast
OSPF process is 1, AREA: 0, Router ID: 192.168.1.1
Cost: 1, Transmit Delay is 1 sec, Priority 1
Hello interval is 10, Dead timer is 40, Retransmit is 5
OSPF INTF State is IDr
Designated Router ID: 192.168.1.1, Interface address 192.168.2.1
Neighbor Count is 0, Adjacent neighbor count is 0
Router-A#sh ip ospf neighbor ！查看邻居状态
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OSPF process: 1
AREA: 0
Neighbor ID Pri State DeadTime Neighbor Addr Interface
192.168.2.1 0 FULL/DROTHER 109 192.168.1.2 Serial1/1
192.168.4.1 0 FULL/DROTHER 96 192.168.1.3 Serial1/1
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