BGP联邦
要求：
1.AS1存在两个环回，192.168.1.0/24不能宣告在任何协议中，另一个为10.1.1.0/24
AS3存在两个环回，192.168.2.0/24不能宣告在任何协议中，另一个为10.1.2.0/24
最终要求两个环回可以互相访问
2.整个AS2为172.16.0.0/16
3.AS之间骨干链路随意设置
4.使用BGP让整个网络环回互通
5.R2/3/4使用BGP联邦64512，R5/6/7使用BGP联邦54613
6.减少路由条目
拓扑如下
AS1与AS2之间使用12.1.1.0/24，AS2与AS3使用78.1.1.0/24
AS2内网划分完使用的172.16.0.0/20
一、
配置完地址先启用IGP协议（OSPF）
R2
ospf 1 router-id 2.2.2.2
area 0.0.0.0
network 172.16.0.0 0.0.15.255
network 172.16.32.0 0.0.15.255
network 172.16.128.0 0.0.15.255R3
ospf 1 router-id 3.3.3.3
area 0.0.0.0
network 172.16.0.0 0.0.15.255
network 172.16.16.0 0.0.15.255
network 172.16.144.0 0.0.15.255 R4
ospf 1 router-id 4.4.4.4
area 0.0.0.0
network 172.16.16.0 0.0.15.255
network 172.16.80.0 0.0.15.255
network 172.16.160.0 0.0.15.255 R5
ospf 1 router-id 5.5.5.5
area 0.0.0.0
network 172.16.32.0 0.0.15.255
network 172.16.48.0 0.0.15.255
network 172.16.176.0 0.0.15.255 R6
ospf 1 router-id 6.6.6.6
area 0.0.0.0
network 172.16.48.0 0.0.15.255
network 172.16.64.0 0.0.15.255
network 172.16.192.0 0.0.15.255 R7
ospf 1 router-id 7.7.7.7
area 0.0.0.0
network 172.16.64.0 0.0.15.255
network 172.16.80.0 0.0.15.255
network 172.16.208.0 0.0.15.255 二、
建立BGP邻居
AS1与AS2使用直连接口建立邻居
R1
bgp 1
router-id 1.1.1.1
peer 12.1.1.2 as-number 2 R2
bgp 64512
router-id 2.2.2.2
confederation id 2//声明大AS号
peer 12.1.1.1 as-number 1 AS2与AS3之间使用环回接口建立邻居
R7
bgp 64513
router-id 7.7.7.7
confederation id 2
peer 10.1.2.1 as-number 3
peer 10.1.2.1 ebgp-max-hop 2
peer 10.1.2.1 connect-interface LoopBack0
ip route-static 10.1.2.1 255.255.255.255 78.1.1.2//到对端环回的路由R8
bgp 3
router-id 8.8.8.8
peer 172.16.208.1 as-number 2
peer 172.16.208.1 ebgp-max-hop 2
peer 172.16.208.1 connect-interface LoopBack1
ip route-static 172.16.208.1 255.255.255.255 78.1.1.1AS2之间建立IBGP邻居
R2
bgp 64512
confederation peer-as 64513//声明对端小AS号
peer 172.16.144.1 as-number 64512
peer 172.16.144.1 connect-interface LoopBack0
peer 172.16.176.1 as-number 64513
peer 172.16.176.1 ebgp-max-hop 255 //联邦之间为EBGP邻居关系
peer 172.16.176.1 connect-interface LoopBack0R3
bgp 64512
router-id 3.3.3.3
confederation id 2
peer 172.16.128.1 as-number 64512
peer 172.16.128.1 connect-interface LoopBack0
peer 172.16.160.1 as-number 64512
peer 172.16.160.1 connect-interface LoopBack0R4
bgp 64512
router-id 4.4.4.4
confederation id 2
confederation peer-as 64513
peer 172.16.144.1 as-number 64512
peer 172.16.144.1 connect-interface LoopBack0
peer 172.16.208.1 as-number 64513
peer 172.16.208.1 ebgp-max-hop 255
peer 172.16.208.1 connect-interface LoopBack0R5
bgp 64513
router-id 5.5.5.5
confederation id 2
confederation peer-as 64512
peer 172.16.128.1 as-number 64512
peer 172.16.128.1 ebgp-max-hop 255
peer 172.16.128.1 connect-interface LoopBack0
peer 172.16.192.1 as-number 64513
peer 172.16.192.1 connect-interface LoopBack0R6
bgp 64513
router-id 6.6.6.6
confederation id 2
peer 172.16.176.1 as-number 64513
peer 172.16.176.1 connect-interface LoopBack0
peer 172.16.208.1 as-number 64513
peer 172.16.208.1 connect-interface LoopBack0R7
bgp 64513
confederation peer-as 64512
peer 172.16.160.1 as-number 64512
peer 172.16.160.1 ebgp-max-hop 255
peer 172.16.160.1 connect-interface LoopBack0
peer 172.16.192.1 as-number 64513
peer 172.16.192.1 connect-interface LoopBack0四、
通告路由
R1只能通告10.1.1.0/24网段
bgp 1
network 10.1.1.0 255.255.255.0
ip route-static 10.1.1.0 255.255.255.0 NULL0R2将汇总路由通告到BGP
bgp 64512
network 172.16.0.0
ip route-static 172.16.0.0 255.255.0.0 NULL0R7跟R2一样
bgp 64513
network 172.16.0.0
ip route-static 172.16.0.0 255.255.0.0 NULL0R8跟R1一样
bgp 3
network 10.1.2.0 255.255.255.0
ip route-static 10.1.2.0 255.255.255.0 NULL0R4因为IBGP水平分割原因收不到AS1的路由
Total Number of Routes: 2
Network NextHop MED LocPrf PrefVal Path/Ogn
*>i 10.1.2.0/24 172.16.208.1 0 100 0 (64513) 3i
*>i 172.16.0.0 172.16.208.1 0 100 0 (64513)i所以在R3上配置为RR指定R4为客户端
bgp 64512
peer 172.16.160.1 reflect-clientR5同理收不到AS3路由
R6指定R5为客户端
bgp 64513
peer 172.16.176.1 reflect-client此时AS2内部路由全部可以传递
AS1pinAS3
ping -a 10.1.1.1 10.1.2.1
PING 10.1.2.1: 56 data bytes, press CTRL_C to break
Reply from 10.1.2.1: bytes=56 Sequence=1 ttl=251 time=80 ms
Reply from 10.1.2.1: bytes=56 Sequence=2 ttl=251 time=50 ms
Reply from 10.1.2.1: bytes=56 Sequence=3 ttl=251 time=50 ms
Reply from 10.1.2.1: bytes=56 Sequence=4 ttl=251 time=30 ms
Reply from 10.1.2.1: bytes=56 Sequence=5 ttl=251 time=50 ms
--- 10.1.2.1 ping statistics ---
5 packet(s) transmitted
5 packet(s) received
0.00% packet loss
round-trip min/avg/max = 30/52/80 ms 五、
AS1的192.168.1.0/24与AS3的192.168.2.0/24互通
这里使用GRP VPN
R1
interface LoopBack0
ip address 192.168.1.1 255.255.255.128
interface Tunnel0/0/0
ip address 10.1.1.129 255.255.255.128
tunnel-protocol gre
source 10.1.1.1 //使用通告进BGP的地址
destination 10.1.2.1
ospf network-type broadcast
ip route-static 0.0.0.0 0.0.0.0 Tunnel0/0/0//使用缺省将AS1，AS3不能通告路由协议的网段连通R8
interface LoopBack0
ip address 192.168.2.1 255.255.255.128
interface Tunnel0/0/0
ip address 10.1.2.129 255.255.255.128
tunnel-protocol gre
source 10.1.2.1
destination 10.1.1.1
ospf network-type broadcast
ip route-static 0.0.0.0 0.0.0.0 Tunnel0/0/0R1pingR8
[Huawei] ping -a 192.168.1.1 192.168.2.1
PING 192.168.2.1: 56 data bytes, press CTRL_C to break
Reply from 192.168.2.1: bytes=56 Sequence=1 ttl=255 time=60 ms
Reply from 192.168.2.1: bytes=56 Sequence=2 ttl=255 time=40 ms
Reply from 192.168.2.1: bytes=56 Sequence=3 ttl=255 time=50 ms
Reply from 192.168.2.1: bytes=56 Sequence=4 ttl=255 time=40 ms
Reply from 192.168.2.1: bytes=56 Sequence=5 ttl=255 time=50 ms
--- 192.168.2.1 ping statistics ---
5 packet(s) transmitted
5 packet(s) received
0.00% packet loss
round-trip min/avg/max = 40/48/60 ms