Cisco-配置EBGP实例
一、网络拓扑图
二、IP地址规划表
设备 | 接口 | IP地址 |
R1 | G0/0 | 10.0.0.1/30 |
R1 | G0/1 | 40.0.0.1/30 |
R1 | G0/2 | 192.168.10.254/24 |
R2 | G0/0 | 10.0.0.2/30 |
R2 | G0/1 | 20.0.0.2/30 |
R2 | G0/2 | 192.168.20.254/24 |
R3 | G0/0 | 30.0.0.1/30 |
R3 | G0/1 | 20.0.0.1/30 |
R3 | G0/2 | 192.168.30.254/24 |
R4 | G0/0 | 40.0.0.2/30 |
R4 | G0/1 | 30.0.0.2/30 |
R4 | G0/2 | 192.168.40.254/24 |
PC0 | Fa0 | 192.168.10.1/24 |
PC1 | Fa0 | 192.168.20.1/24 |
PC2 | Fa0 | 192.168.30.1/24 |
PC3 | Fa0 | 192.168.40.1/24 |
三、操作步骤（IP地址自己配置，这里不做演示）
1、路由器进入BGP配置模式，AS编号分别为1、2、3、4
R1
R1(config)#router bgp 1
R2
R2(config)#router bgp 2
R3
R3(config)#router bgp 3
R4
R4(config)#router bgp 4
2、BGP宣告直连网段
R1
R1(config-router)#network 192.168.10.0 mask 255.255.255.0
R1(config-router)#network 10.0.0.0 mask 255.255.255.252
R1(config-router)#network 40.0.0.0 mask 255.255.255.252
R2
R2(config-router)#network 192.168.20.0 mask 255.255.255.0
R2(config-router)#network 10.0.0.0 mask 255.255.255.252
R2(config-router)#network 20.0.0.0 mask 255.255.255.252
R3
R3(config-router)#network 192.168.30.0 mask 255.255.255.0
R3(config-router)#network 20.0.0.0 mask 255.255.255.252
R3(config-router)#network 30.0.0.0 mask 255.255.255.252
R4
R4(config-router)#network 192.168.40.0 mask 255.255.255.0
R4(config-router)#network 30.0.0.0 mask 255.255.255.252
R4(config-router)#network 40.0.0.0 mask 255.255.255.252
3、指定邻居的ip和AS编号
R1
R1(config-router)#neighbor 10.0.0.2 remote-as 2
R1(config-router)#neighbor 40.0.0.2 remote-as 4
R2
R2(config-router)#neighbor 10.0.0.1 remote-as 1
R2(config-router)#neighbor 20.0.0.1 remote-as 3
R3
R3(config-router)#neighbor 20.0.0.2 remote-as 2
R3(config-router)#neighbor 30.0.0.2 remote-as 4
R4
R4(config-router)#neighbor 30.0.0.1 remote-as 3
R4(config-router)#neighbor 40.0.0.1 remote-as 1
4、验证BGP
R1
R2
R3
R4
PC0访问PC1、PC2和PC3
