一：实验拓扑：
二：实验要求：
1、AS1中存在两个环回，一个地址为192.168.1.0/24，该地址不能在任何协议中宣告;
AS3中存在两个环回一个地址为192.168.2.0/24，该地址不能在任何协议中宣告，最终要求这 两个环回可以ping通;
2、整个AS2的IP地址为172.16.0.0/16，R3-R7上各有一个业务网段，请合理划分; 并且其内部配 置OSPF协议
3、As间的骨干链路IP地址随意定制;
4、使用Bgp协议让整个网络所有设备的环回可以互相访问;
5、减少路由条目数量，避免环路出现；
三：实验步骤：
1:配置IP地址：
R1：
[R1-GigabitEthernet0/0/0]ip add 12.1.1.1 24
May 11 2024 13:35:08-08:00 R1 %%01IFNET/4/LINK_STATE(l)[1]:The line protocol IP
on the interface GigabitEthernet0/0/0 has entered the UP state.
[R1-LoopBack0]ip add 172.16.0.1 32
[R1-LoopBack1]ip add 192.168.1.1 24
R2：
[R2-GigabitEthernet0/0/0]ip add 12.1.1.2 24
May 11 2024 13:37:29-08:00 R2 %%01IFNET/4/LINK_STATE(l)[0]:The line protocol IP
on the interface GigabitEthernet0/0/0 has entered the UP state.
[R2-GigabitEthernet0/0/1]ip add 172.16.1.1 30
May 11 2024 13:37:55-08:00 R2 %%01IFNET/4/LINK_STATE(l)[1]:The line protocol IP
on the interface GigabitEthernet0/0/1 has entered the UP state.
[R2-GigabitEthernet0/0/2]ip add 172.16.1.21 30
May 11 2024 13:38:13-08:00 R2 %%01IFNET/4/LINK_STATE(l)[2]:The line protocol IP
on the interface GigabitEthernet0/0/2 has entered the UP state.
[R2-LoopBack0]ip add 172.16.0.2 32
R3：
[R3-GigabitEthernet0/0/0]ip add 172.16.1.2 30
May 11 2024 13:40:42-08:00 R3 %%01IFNET/4/LINK_STATE(l)[0]:The line protocol IP
on the interface GigabitEthernet0/0/0 has entered the UP state.
[R3-GigabitEthernet0/0/1]ip add 172.16.1.5 30
May 11 2024 13:41:01-08:00 R3 %%01IFNET/4/LINK_STATE(l)[1]:The line protocol IP
on the interface GigabitEthernet0/0/1 has entered the UP state.
[R3-LoopBack0]ip add 172.16.0.3 32
[R3-LoopBack1]ip add 172.16.3.1 24
R4：
[R4-GigabitEthernet0/0/0]ip add 172.16.1.6 30
[R4-GigabitEthernet0/0/1]ip add 172.16.1.9 30
[R4-LoopBack0]ip add 172.16.0.3 32
[R4-LoopBack1]ip add 172.16.4.1 24
R5:
[R5-GigabitEthernet0/0/0]ip add 172.16.1.22 30
[R5-GigabitEthernet0/0/1]ip add 172.16.1.17 30
[R5-LoopBack0]ip add 172.16.0.5 32
[R5-LoopBack1]ip add 172.16.5.1 24
R6:
[R6-GigabitEthernet0/0/0]ip add 172.16.1.18 30
[R6-GigabitEthernet0/0/1]ip add 172.16.1.13 30
[R6-LoopBack0]ip add 172.16.0.6 32
[R6-LoopBack1]ip add 172.16.6.1 24
R7:
[R7-GigabitEthernet0/0/0]ip add 172.16.1.14 30
[R7-GigabitEthernet0/0/1]ip add 172.16.1.10 30
[R7-GigabitEthernet0/0/2]ip add 34.1.1.1 24
[R7-LoopBack0]ip add 172.16.0.7 32
[R7-LoopBack1]ip add 172.16.7.9 24
R8:
[R8-GigabitEthernet0/0/0]ip add 34.1.1.2 24
[R8-LoopBack0]ip add 172.16.0.8 32
[R8-LoopBack1]ip add 192.168.2.1 24
2:AS内部OSPF互通
R2：
[R2]ospf 1 router-id 2.2.2.2
[R2-ospf-1]area 0
[R2-ospf-1-area-0.0.0.0]network 172.16.1.1 0.0.0.0
[R2-ospf-1-area-0.0.0.0]network 172.16.1.21 0.0.0.0
[R2-ospf-1-area-0.0.0.0]network 172.16.0.2 0.0.0.0
R3：
[R3]ospf 1 router-id 3.3.3.3
[R3-ospf-1]area 0
[R3-ospf-1-area-0.0.0.0]network 172.16.1.2 0.0.0.0
[R3-ospf-1-area-0.0.0.0]network 172.16.1.5 0.0.0.0
[R3-ospf-1-area-0.0.0.0]network 172.16.0.3 0.0.0.0
[R3-ospf-1-area-0.0.0.0]network 172.16.3.0 0.0.0.255
R4：
[R4]ospf 1 router-id 4.4.4.4
[R4-ospf-1]area 0
[R4-ospf-1-area-0.0.0.0]network 172.16.1.6 0.0.0.0
[R4-ospf-1-area-0.0.0.0]network 172.16.1.9 0.0.0.0
[R4-ospf-1-area-0.0.0.0]network 172.16.0.4 0.0.0.0
[R4-ospf-1-area-0.0.0.0]network 172.16.4.0 0.0.0.255
R5：
[R5]ospf 1 router-id 5.5.5.5
[R5-ospf-1]area 0
[R5-ospf-1-area-0.0.0.0]network 172.16.1.22 0.0.0.0
[R5-ospf-1-area-0.0.0.0]network 172.16.1.17 0.0.0.0
[R5-ospf-1-area-0.0.0.0]network 172.16.0.5 0.0.0.0
[R5-ospf-1-area-0.0.0.0]network 172.16.5.0 0.0.0.255
R6：
[R6]ospf 1 router-id 6.6.6.6
[R6-ospf-1]area 0
[R6-ospf-1-area-0.0.0.0]network 172.16.1.18 0.0.0.0
[R6-ospf-1-area-0.0.0.0]network 172.16.1.13 0.0.0.0
[R6-ospf-1-area-0.0.0.0]network 172.16.0.6 0.0.0.0
[R6-ospf-1-area-0.0.0.0]network 172.16.6.0 0.0.0.255
R7：
[R7]ospf 1 router-id 7.7.7.7
[R7-ospf-1]area 0
[R7-ospf-1-area-0.0.0.0]network 172.16.1.14 0.0.0.0
[R7-ospf-1-area-0.0.0.0]network 172.16.1.10 0.0.0.0
[R7-ospf-1-area-0.0.0.0]network 172.16.0.7 0.0.0.0
[R7-ospf-1-area-0.0.0.0]network 172.16.7.0 0.0.0.255
3：BGP建邻
R1：
[R1]bgp 1
[R1-bgp]peer 12.1.1.2 as-number 2
R2：
[R2]bgp 64512
[R2-bgp]confederation id 2
[R2-bgp]confederation peer-as 64513
[R2-bgp]peer 12.1.1.1 as-number 1
[R2-bgp]peer 172.16.1.2 as 64512
[R2-bgp]peer 172.16.1.2 next-hop-local
[R2-bgp]peer 172.16.1.22 as 64513
[R2-bgp]peer 172.16.1.22 next-hop-local
R3：
[R3]bgp 64512
[R3-bgp]confederation id 2
[R3-bgp]peer 172.16.1.1 as 64512
[R3-bgp]peer 172.16.1.1 next-hop-local
[R3-bgp]peer 172.16.1.6 as 64512
[R3-bgp]peer 172.16.1.6 next-hop-local
R4：
[R4]bgp 64512
[R4-bgp]confederation id 2
[R4-bgp]peer 172.16.1.5 as 64512
[R4-bgp]peer 172.16.1.5 next-hop-local
R5：
[R5]bgp 64513
[R5-bgp]confederation id 2
[R5-bgp]confederation peer-as 64512
[R5-bgp]peer 172.16.1.21 as 64512
[R5-bgp]peer 172.16.1.21 next-hop-local
[R5-bgp]peer 172.16.1.18 as 64513
[R5-bgp]peer 172.16.1.18 next-hop-local
R6：
[R6]bgp 64513
[R6-bgp]confederation id 2
[R6-bgp]peer 172.16.1.17 as 64513
[R6-bgp]peer 172.16.1.17 next-hop-local
[R6-bgp]peer 172.16.1.14 as 64513
[R6-bgp]peer 172.16.1.14 next-hop-local
R7：
[R7]bgp 64513
[R7-bgp]confederation id 2
[R7-bgp]peer 34.1.1.2 as 3
[R7-bgp]peer 34.1.1.2 next-hop-local
[R7-bgp]peer 172.16.1.13 as 64513
[R7-bgp]peer 172.16.1.13 next-hop-local
[R7-bgp]peer 172.16.1.9 as 64512
[R7-bgp]peer 172.16.1.9 next-hop-local
R8：
[R8]bgp 3
[R8-bgp]peer 34.1.1.1 as 2
R3路由反射
[R3]bgp 64512
[R3-bgp]peer 172.16.1.6 reflect-client
添加空接口放环
[R2]ip route-static 172.16.0.0 21 NULL0
[R2]bgp 64512
[R2-bgp]net
[R2-bgp]network 172.16.0.0 21
[R7]ip route-static 172.16.0.0 21 NULL 0
[R7]bgp 64513
[R7-bgp]net
[R7-bgp]network 172.16.0.0 21
R1和R8搭建GRE环境
R1
[R1]int t 0/0/0
[R1-Tunnel0/0/0]ip add 10.1.1.1 24
[R1-Tunnel0/0/0]tunnel-protocol gre
[R1-Tunnel0/0/0]source 1.1.1.1
[R1-Tunnel0/0/0]description 10.1.2.1
R8
[R8]int t 0/0/0
[R8-Tunnel0/0/0]ip add 10.1.1.2 24
[R8-Tunnel0/0/0]tunnel-protocol gre
[R8-Tunnel0/0/0]source 1.1.2.1
[R8-Tunnel0/0/0]description 10.1.2.2
[R1]ip route-static 192.168.1.0 24 10.1.1.2
[R8]ip route-static 192.168.2.0 24 10.1.1.1
