实验内容：

通过本实验验证bgp路由反射器的规则

   1. 从client收到的路由更新，反射到non-client和client，同时发送给EBGP邻居

   2. 从non-client收到的路由更新，只反射到client，同时发送给EBGP邻居

   3. 从EBGP邻居收到的路由更新，发送到所有的non-client和client

实验拓扑如图

实验配置如下：

 基本配置：

路由器1

interface GigabitEthernet 0/0
 no switchport
 ip address 10.1.12.1 255.255.255.252
!
interface Loopback 0
 ip address 1.1.1.1 255.255.255.255
!
interface Loopback 1
 ip address 1.1.2.1 255.255.255.255
!
interface Loopback 2
 ip address 1.1.3.1 255.255.255.255
!
interface Loopback 4
 ip address 1.1.4.1 255.255.255.255
!
router bgp 100
 neighbor 10.1.12.2 remote-as 200
  network 1.1.1.1 mask 255.255.255.255
  network 1.1.2.1 mask 255.255.255.255
  network 1.1.3.1 mask 255.255.255.255
  network 1.1.4.1 mask 255.255.255.255

 路由器2

interface GigabitEthernet 0/0
 no switchport
 ip address 10.1.12.2 255.255.255.252
!
interface GigabitEthernet 0/1
 no switchport
 ip address 10.1.23.1 255.255.255.252
!
interface Loopback 0
 ip address 2.2.2.2 255.255.255.255
!
router bgp 200
 neighbor 3.3.3.3 remote-as 200
 neighbor 3.3.3.3 update-source Loopback 0
 neighbor 10.1.12.1 remote-as 100
  neighbor 3.3.3.3 next-hop-self
!
router ospf 200
 router-id 2.2.2.2
 network 2.2.2.2 0.0.0.0 area 0
 network 10.1.23.1 0.0.0.0 area 0

路由器3

!
interface GigabitEthernet 0/0
 no switchport
 ip address 10.1.34.1 255.255.255.252
!
interface GigabitEthernet 0/1
 no switchport
 ip address 10.1.23.2 255.255.255.252
!
interface GigabitEthernet 0/2
 no switchport
 ip address 10.1.35.1 255.255.255.252
!
interface Loopback 0
 ip address 3.3.3.3 255.255.255.255
!
router bgp 200
 neighbor 2.2.2.2 remote-as 200
 neighbor 2.2.2.2 update-source Loopback 0
 neighbor 4.4.4.4 remote-as 200
 neighbor 4.4.4.4 update-source Loopback 0
 neighbor 5.5.5.5 remote-as 200
 neighbor 5.5.5.5 update-source Loopback 0
  neighbor 2.2.2.2 next-hop-self
!
router ospf 200
 router-id 3.3.3.3
 network 3.3.3.3 0.0.0.0 area 0
 network 10.1.23.2 0.0.0.0 area 0
 network 10.1.34.1 0.0.0.0 area 0
 network 10.1.35.1 0.0.0.0 area 0

路由器4

interface GigabitEthernet 0/0
 no switchport
 ip address 10.1.34.2 255.255.255.252
!
interface Loopback 0
 ip address 4.4.4.4 255.255.255.255
!         
router bgp 200
 neighbor 3.3.3.3 remote-as 200
 neighbor 3.3.3.3 update-source Loopback 0
!
router ospf 200
 router-id 4.4.4.4
 network 4.4.4.4 0.0.0.0 area 0
 network 10.1.34.2 0.0.0.0 area 0

路由器5

interface GigabitEthernet 0/2
 no switchport
 ip address 10.1.35.2 255.255.255.252
!
interface Loopback 0
 ip address 5.5.5.5 255.255.255.255
!         
router bgp 200
 neighbor 3.3.3.3 remote-as 200
 neighbor 3.3.3.3 update-source Loopback 0
!
router ospf 200
 route-id 5.5.5.5
 network 5.5.5.5 0.0.0.0 area 0
 network 10.1.35.2 0.0.0.0 area 0

此时的R4,R5的bgp表上应该是没有任何路由的，因为ibgp之间存在水平分割

接下来通过配置路由反射器来实现路由的传递

路由器3

router bgp 200
  neighbor 2.2.2.2 route-reflector-client         //将R2设置为client

不配置的ibgp邻居默认为no-client，此时的R4，R5上就可以看到R1传过来的路由了，路由反射器的规则1就验证完成了

路由器4

router bgp 200
  network 4.4.4.4 mask 255.255.255.255           //用于验证规则2

路由器5

router bgp 200
  network 5.5.5.5 mask 255.255.255.255           //用于验证规则2

这时的R2可以收到R4,R5发来的路由，而R4,R5之间收不到彼此发送的路由---规则2

此时R2,R4,R5的bgp表如下