[experiment sharing] CCIE BGP reflector experiment

​ The experiment purpose :

l master BGP Operating principle of reflector

l Understand the use and benefits of reflectors

Experimental instructions ：

l Practice through this experiment , It can be used flexibly BGP Reflector

Experimental environment ：

l Three support SPSERVICES Of IOS The router

l Through line

The topology ：

The experimental steps ：

R1(config)#interface f0/0

R1(config-if)#ip address 12.1.1.1 255.255.255.0

R1(config-if)#no shutdown

R1(config-if)#int lo 0

R1(config-if)#ip address 1.1.1.1 255.255.255.255

R1(config)#router ospf 110

R1(config-router)#router-id 1.1.1.1

R1(config-router)#network 1.1.1.1 0.0.0.0 a 0

R1(config-router)#network 12.1.1.1 0.0.0.0 a 0

R1(config)#router bgp 100

R1(config-router)#bgp router-id 1.1.1.1

R1(config-router)#neighbor 2.2.2.2 remote-as 100

R1(config-router)#neighbor 2.2.2.2 update-source loopback 0

R1(config-router)#neighbor 2.2.2.2 next-hop-self{ When R1 adopt EBGP The learned route is passed to 2.2.2.2 Tell me when 2.2.2.2, When 2.2.2.2 When this route is received, the next hop is R1 The ring return port of }

R2(config)#interface f0/0

R2(config-if)#ip address 12.1.1.2 255.255.255.0

R2(config-if)#no shutdown

R2(config-if)#int f1/0

R2(config-if)#ip address 23.1.1.2 255.255.255.0

R2(config-if)#no shutdown

R2(config-if)#int lo 0

R2(config-if)#ip address 2.2.2.2 255.255.255.255

R2(config)#router ospf 110

R2(config-router)#router-id 2.2.2.2

R2(config-router)#network 12.1.1.2 0.0.0.0 a 0

R2(config-router)#network 23.1.1.2 0.0.0.0 a 0

R2(config-router)#network 2.2.2.2 0.0.0.0 a 0

R2(config)#router bgp 100

R2(config-router)#bgp router-id 2.2.2.2

R2(config-router)#neighbor 1.1.1.1 remote-as 100

R2(config-router)#neighbor 1.1.1.1 update-source lo 0

R2(config-router)#neighbor 1.1.1.1 route-reflector-client {1.1.1.1 Is my client }

R2(config-router)#neighbor 3.3.3.3 remote-as 100

R2(config-router)#neighbor 3.3.3.3 update-source lo 0

R2(config-router)#neighbor 3.3.3.3 route-reflector-client{3.3.3.3 Is my client }
R3(config)#interface f1/0

R3(config-if)#ip address 23.1.1.3 255.255.255.0

R3(config-if)#no shutdown

R3(config-if)#int lo 0

R3(config-if)#ip address 3.3.3.3 255.255.255.255

R3(config)#router ospf 110

R3(config-router)#router-id 3.3.3.3

R3(config-router)#network 23.1.1.3 0.0.0.0 a 0

R3(config-router)#network 3.3.3.3 0.0.0.0 a 0

R3(config)#router bgp 100

R3(config-router)#bgp router-id 3.3.3.3

R3(config-router)#neighbor 2.2.2.2 remote-as 100

R3(config-router)#neighbor 2.2.2.2 update-source lo 0

R3(config-router)#neighbor 2.2.2.2 next-hop-self

adopt RR（ Reflector ） Technology can break IBGP The horizontal division of , adopt RR Technology can reduce IBGP Build a neighborhood , such as R1,R2,R3 Learn the corresponding route , Must establish 3 It's a neighborhood ,R1 and R2,R2 and R3,R1 and R3. and RR Technology

It only needs R1,R3 Respectively and R2 Just build a neighbor .

R1 Announce routing

R1(config)#int lo 11

R1(config-if)#ip address 11.11.11.11 255.255.255.255

R1(config)#router bgp 100

R1(config-router)#network 11.11.11.11 mask 255.255.255.255

verification ：

R2#show ip bgp 11.11.11.11

BGP routing table entry for 11.11.11.11/32, version 2

Paths: (1 available, best #1, table Default-IP-Routing-Table)

Flag: 0x820

Advertised to update-groups:

2

Local, (Received from a RR-client) { From the client （1.1.1.1） Learn routing 11.11.11.11}

1.1.1.1 (metric 2) from 1.1.1.1 (1.1.1.1)

Origin IGP, metric 0, localpref 100, valid, internal, best

R3#show ip bgp 11.11.11.11

BGP routing table entry for 11.11.11.11/32, version 2

Paths: (1 available, best #1, table Default-IP-Routing-Table)

Flag: 0x820

Not advertised to any peer

Local

1.1.1.1 (metric 3) from 2.2.2.2 (2.2.2.2)

Origin IGP, metric 0, localpref 100, valid, internal, best

Originator: 1.1.1.1, Cluster list: 2.2.2.2{1.1.1.1 Generated route , adopt RR（2.2.2.2） Reflect to 3.3.3.3}

summary ：

adopt RR Technical reasonable break IBGP Horizontal segmentation , It is more convenient to implement .

RR principle ：

The route from the client , RR It will be passed to my client , Non client , EBGP neighbor .

from EBGP The route from neighbors , RR It will be passed to my client , Non client , EBGP neighbor .

Routes from non clients , RR It will be passed to my client , EBGP neighbor , It will not be passed to non clients .