A-A+
	实验五:BGP的路由反射器
实验目标:
1、熟练BGP的基本配置。
2、掌握BGP路由反射器的原理。
实验TOP:
物理拓扑
逻辑拓扑
基本配置
R1的配置:
- !
 - hostname r1
 - !
 - interface Loopback0
 - ip address 1.1.1.1255.255.255.0
 - !
 - interface Ethernet0/0
 - no shu
 - !
 - interface Ethernet0/0.14
 - encapsulation dot1Q 14
 - ip address 10.1.1.1255.255.255.0
 - no shu
 - !
 - interface Ethernet0/0.15
 - encapsulation dot1Q 15
 - ip address 20.1.1.1255.255.255.0
 - no shu
 - !
 - interface Serial1/0
 - ip address 12.1.1.1255.255.255.0
 - no shu
 - !
 - interface Serial2/0
 - ip address 13.1.1.1255.255.255.0
 - no shu
 - !
 - router ospf 10
 - network 10.1.1.00.0.0.255 area 0
 - network 12.1.1.00.0.0.255 area 0
 - network 13.1.1.00.0.0.255 area 0
 - network 20.1.1.00.0.0.255 area 0
 - !
 - router bgp 10
 - no synchronization
 - bgp router-id 1.1.1.1
 - network 1.1.1.0mask 255.255.255.0
 - neighbor 10.1.1.4remote-as 20
 - neighbor 12.1.1.2remote-as 10
 - neighbor 13.1.1.3remote-as 10
 - neighbor 20.1.1.5remote-as 10
 - no auto-summary
 - !
 
R2的配置:
- !
 - hostname r2
 - !
 - interface Loopback0
 - ip address 2.2.2.2255.255.255.0
 - !
 - !
 - interface Serial2/0
 - ip address 12.1.1.2255.255.255.0
 - no shu
 - !
 - router ospf 10
 - network 12.1.1.00.0.0.255 area 0
 - !
 - router bgp 10
 - no synchronization
 - bgp router-id 2.2.2.2
 - network 2.2.2.0mask 255.255.255.0
 - neighbor 12.1.1.1remote-as 10
 - no auto-summary
 - !
 
R3的配置:
- !
 - hostname r3
 - !
 - interface Loopback0
 - ip address 3.3.3.3255.255.255.0
 - !
 - interface Serial1/0
 - ip address 13.1.1.3255.255.255.0
 - no shu
 - ! www.luyouqiwang.com
 - !
 - router ospf 10
 - network 13.1.1.00.0.0.255 area 0
 - !
 - router bgp 10
 - no synchronization
 - bgp router-id 3.3.3.3
 - network 3.3.3.0mask 255.255.255.0
 - neighbor 13.1.1.1remote-as 10
 - no auto-summary
 - !
 
R4配置:
- !
 - hostname r4
 - !
 - interface Loopback0
 - ip address 4.4.4.4255.255.255.0
 - !
 - interface Ethernet0/0
 - no shu
 - !
 - interface Ethernet0/0.14
 - encapsulation dot1Q 14
 - ip address 10.1.1.4255.255.255.0
 - no shu
 - !
 - !
 - router ospf 10
 - network 10.1.1.00.0.0.255 area 0
 - !
 - router bgp 20
 - no synchronization
 - bgp router-id 4.4.4.4
 - network 4.4.4.0mask 255.255.255.0
 - neighbor 10.1.1.1remote-as 10
 - no auto-summary
 - !
 
R5配置:
- !
 - hostname r5
 - !
 - interface Loopback0
 - ip address 5.5.5.5255.255.255.0
 - !
 - interface Ethernet0/0
 - no shu
 - !
 - interface Ethernet0/0.15
 - encapsulation dot1Q 15
 - ip address 20.1.1.5255.255.255.0
 - no shu
 - !
 - !
 - router ospf 10
 - network 20.1.1.00.0.0.255 area 0
 - !
 - router bgp 10
 - no synchronization
 - bgp router-id 5.5.5.5
 - network 5.5.5.0mask 255.255.255.0
 - neighbor 20.1.1.1remote-as 10
 - no auto-summary
 - !
 
验证:
下面我们查看一下每个路由器的BGP表,目的是验证BGP中路由条目传递的原则。
r1的BGP表
- r1#show ip bgp
 - BGP table version is 6, local router ID is 1.1.1.1
 - Status codes: s suppressed, d damped, hhistory, * valid, > best, i - internal,
 - r RIB-failure, S Stale
 - Origin codes: i - IGP, e - EGP, ? -incomplete
 - Network Next Hop Metric LocPrf Weight Path
 - *> 1.1.1.0/24 0.0.0.0 0 32768 i
 - *>i2.2.2.0/24 12.1.1.2 0 100 0 i
 - *>i3.3.3.0/24 13.1.1.3 0 100 0 i
 - *> 4.4.4.0/24 10.1.1.4 0 0 20 i
 - *>i5.5.5.0/24 20.1.1.5 0 100 0 i
 
r2的BGP表
- r2#show ip bgp
 - BGP table version is 4, local router ID is 2.2.2.2
 - Status codes: s suppressed, d damped, hhistory, * valid, > best, i - internal,
 - r RIB-failure, S Stale
 - Origin codes: i - IGP, e - EGP, ? -incomplete
 - Network Next Hop Metric LocPrf Weight Path
 - *>i1.1.1.0/24 12.1.1.1 0 100 0 i
 - *> 2.2.2.0/24 0.0.0.0 0 32768 i
 - *>i4.4.4.0/24 10.1.1.4 0 100 0 20 i
 
r3的BGP表
- r3#show ip bgp
 - BGP table version is 4, local router ID is 3.3.3.3
 - Status codes: s suppressed, d damped, hhistory, * valid, > best, i - internal,
 - r RIB-failure, S Stale
 - Origin codes: i - IGP, e - EGP, ? -incomplete
 - Network Next Hop Metric LocPrf Weight Path
 - *>i1.1.1.0/24 13.1.1.1 0 100 0 i
 - *> 3.3.3.0/24 0.0.0.0 0 32768 i
 - *>i4.4.4.0/24 10.1.1.4 0 100 0 20 i
 
r4的BGP表
- r4#show ip bgp
 - BGP table version is 6, local router ID is 4.4.4.4
 - Status codes: s suppressed, d damped, hhistory, * valid, > best, i - internal,
 - r RIB-failure, S Stale
 - Origin codes: i - IGP, e - EGP, ? -incomplete
 - Network Next Hop Metric LocPrf Weight Path
 - *> 1.1.1.0/24 10.1.1.1 0 0 10 i
 - *> 2.2.2.0/24 10.1.1.1 0 10 i
 - *> 3.3.3.0/24 10.1.1.1 0 10 i
 - *> 4.4.4.0/24 0.0.0.0 0 32768 i
 - *> 5.5.5.0/24 10.1.1.1 0 10 i
 
r5的BGP表
- r5#show ip bgp
 - BGP table version is 4, local router ID is 5.5.5.5
 - Status codes: s suppressed, d damped, hhistory, * valid, > best, i - internal,
 - r RIB-failure, S Stale
 - Origin codes: i - IGP, e - EGP, ? -incomplete
 - Network Next Hop Metric LocPrf Weight Path
 - *>i1.1.1.0/24 20.1.1.1 0 100 0 i
 - *>i4.4.4.0/24 10.1.1.4 0 100 0 20 i
 - *> 5.5.5.0/24 0.0.0.0 0 32768 i
 
从上面每个路由器的BGP表中我们可以得知,默认情况下,IBGP对等体学习到的路由,在满足同步、可达的前提下,仍不会向其他IBGP对等体通告。但会向EBGP对等体通告。,下面我们把R2做成R1路由反射器的客户来观察一下实验现象。配置如下:
r1(config)#router bgp 10
r1(config-router)#neighbor 12.1.1.2route-reflector-client
下面我们来看一R2的BGP表
- r2#show ip bgp
 - BGP table version is 10, local router ID is2.2.2.2
 - Status codes: s suppressed, d damped, hhistory, * valid, > best, i - internal,
 - r RIB-failure, S Stale
 - Origin codes: i - IGP, e - EGP, ? -incomplete
 - Network Next Hop Metric LocPrf Weight Path
 - *>i1.1.1.0/24 12.1.1.1 0 100 0 i
 - *> 2.2.2.0/24 0.0.0.0 0 32768 i
 - *>i3.3.3.0/24 13.1.1.3 0 100 0 i
 - *>i4.4.4.0/24 10.1.1.4 0 100 0 20 i
 - *>i5.5.5.0/24 20.1.1.5 0 100 0 i
 
从上面可以得之,R2从R1学到了所有IBGP对等体的路由条目
下面再来看一下R3和 R5的路由表条目
- r3#show ip bgp
 - BGP table version is 5, local router ID is 3.3.3.3
 - Status codes: s suppressed, d damped, hhistory, * valid, > best, i - internal,
 - r RIB-failure, S Stale
 - Origin codes: i - IGP, e - EGP, ? -incomplete
 - Network Next Hop Metric LocPrf Weight Path
 - *>i1.1.1.0/24 13.1.1.1 0 100 0 i
 - *>i2.2.2.0/24 12.1.1.2 0 100 0 i
 - *> 3.3.3.0/24 0.0.0.0 0 32768 i
 - *>i4.4.4.0/24 10.1.1.4 0 100 0 20 i
 - r5#show ip bgp
 - BGP table version is 5, local router ID is 5.5.5.5
 - Status codes: s suppressed, d damped, hhistory, * valid, > best, i - internal,
 - r RIB-failure, S Stale
 - Origin codes: i - IGP, e - EGP, ? -incomplete
 - Network Next Hop Metric LocPrf Weight Path
 - *>i1.1.1.0/24 20.1.1.1 0 100 0 i
 - *>i2.2.2.0/24 12.1.1.2 0 100 0 i
 - *>i4.4.4.0/24 10.1.1.4 0 100 0 20 i
 - *> 5.5.5.0/24 0.0.0.0 0 32768 i
 
这就证明了路由是从客户处学习到的,将它反射给除了发起该路由的客户外的所有非客户以及客户。反射器从各户收到更新,会向非客户对等体通告。