一、实验拓扑
二、实验需求
1、配置全网互通。BGP中引入IGP路由条目3.3.3.0
2、在AS 100 内采用RIPv2 协议配置IGP
3、在R1 R2 R4 上配置静态路由，保证R1 R2的Loopback 0 接口和R4 的Loopback 0 能建立 TCP会话
4、配置BGP协议，用环回口建立邻居，R3 将33.33.33.0、3.3.3.0 R4将 44.44.44.0 、55.55.55.0通告进BGP进程中
5、配置R3访问55.55.55.55从R2过
- BG路由属性的比较过程中，首先要比较的就是路由信息首选值 Preference Value,也简称为 PreVal. 值越大，优先级越高，默认为 0，Preference Value,不会发送给任何BGP邻居，仅作为本地路由器用来选路使用。
三、实验过程
1、R1的配置
undo ter mo
sys
sysname R1
user-interface console 0
idle-timeout 0 0
int loop 0
ip add 1.1.1.1 24
int g0/0/0
ip add 192.168.13.1 24
int g0/0/1
ip add 192.168.14.1 24
rip
version 2
network 192.168.13.0
network 1.0.0.0
ip route-static 4.4.4.0 255.255.255.0 192.168.14.4
bgp 100
router-id 1.1.1.1
peer 2.2.2.2 as-number 100
peer 2.2.2.2 connect-interface loopback 0
peer 2.2.2.2 next-hop-local
peer 3.3.3.3 as-number 100
peer 3.3.3.3 connect-interface loopback 0
peer 3.3.3.3 next-hop-local
peer 4.4.4.4 as-number 200
peer 4.4.4.4 connect-interface loopback 0
peer 4.4.4.4 ebgp-max-hop
network 3.3.3.0 255.255.255.0
2、R2的配置
undo ter mo
sys
sysname R2
user-interface console 0
idle-timeout 0 0
int loop 0
ip add 2.2.2.2 24
int g0/0/1
ip add 192.168.23.2 24
int g0/0/0
ip add 192.168.24.2 24
rip
version 2
network 192.168.23.0
network 2.0.0.0
ip route-static 4.4.4.0 255.255.255.0 192.168.24.4
bgp 100
router-id 2.2.2.2
peer 1.1.1.1 as-number 100
peer 1.1.1.1 connect-interface loopback 0
peer 1.1.1.1 next-hop-local
peer 3.3.3.3 as-number 100
peer 3.3.3.3 connect-interface loopback 0
peer 3.3.3.3 next-hop-local
peer 4.4.4.4 as-number 200
peer 4.4.4.4 connect-interface loopback 0
peer 4.4.4.4 ebgp-max-hop
network 3.3.3.0 255.255.255.0
3、R3的配置
undo ter mo
sys
sysname R3
user-interface console 0
idle-timeout 0 0
int loop 0
ip add 3.3.3.3 24
int loop 1
ip add 33.33.33.33 24
int g0/0/0
ip add 192.168.13.3 24
int g0/0/1
ip add 192.168.23.3 24
rip
version 2
network 192.168.13.0
network 192.168.23.0
network 3.0.0.0
ip ip-prefix 1 permit 55.55.55.0 24
route-policy 10 permit node 1
if-match ip-prefix 1
apply preferred-value 99
route-policy 10 permit node 2
bgp 100
router-id 3.3.3.3
peer 1.1.1.1 as-number 100
peer 1.1.1.1 connect-interface loopback 0
peer 2.2.2.2 as-number 100
peer 2.2.2.2 connect-interface loopback 0
peer 2.2.2.2 route-policy 10 import
network 33.33.33.0 24
4、R4的配置
undo ter mo
sys
sysname R4
user-interface console 0
idle-timeout 0 0
int loop 0
ip add 4.4.4.4 24
int loop 1
ip add 44.44.44.44 24
int loop 2
ip add 55.55.55.55 24
int g0/0/0
ip add 192.168.14.4 24
int g0/0/1
ip add 192.168.24.4 24
ip route-static 1.1.1.0 255.255.255.0 192.168.14.1
ip route-static 2.2.2.0 255.255.255.0 192.168.24.2
bgp 200
router-id 4.4.4.4
peer 1.1.1.1 as-number 100
peer 1.1.1.1 connect-interface loopback 0
peer 1.1.1.1 ebgp-max-hop
peer 2.2.2.2 as-number 100
peer 2.2.2.2 connect-interface loopback 0
peer 2.2.2.2 ebgp-max-hop
network 44.44.44.0 24
network 55.55.55.0 24
四、实验结果
1、查看R3的BGP路由表
2、查看R1的BGP路由信息
- 在R3 上修改之后，R1 R2 上的PrefVal 值不变，说明了PrefVal 值只作为本地路由器用来选路使用，并不传递给任何BGP 邻居。
3、测试源地址3.3.3.3与44.44.44.44的连通性
评论区