实验要求及拓扑

一、实验思路

1.编写静态路由使R1、R2之间可通和使R4、R5之间可通。

2.使用OSPF使R2、R3、R4之间可通。

3.各自宣告AS区域，中间区域两两之间建邻。

4.注意建邻所使用的端口，外部BGP邻居关系和内部BGP邻居关系的区别。

二、上虚拟机操作

1.IP地址配置

[r1]int g0/0/0

[r1-GigabitEthernet0/0/0]ip add 12.1.1.1 24

[r1-GigabitEthernet0/0/0]int l0

[r1-LoopBack0]ip add 1.1.1.1 24

[r2]int g0/0/0

[r2-GigabitEthernet0/0/0]ip add 12.1.1.2 24

[r2-GigabitEthernet0/0/0]int g0/0/1

[r2-GigabitEthernet0/0/1]ip add 23.1.1.1 24

[r2-GigabitEthernet0/0/1]int l0

[r2-LoopBack0]ip add 2.2.2.2 24

[r3]int g0/0/0

[r3-GigabitEthernet0/0/0]ip add 23.1.1.2 24

[r3-GigabitEthernet0/0/0]int g0/0/1

[r3-GigabitEthernet0/0/1]ip add 34.1.1.1 24

[r3-GigabitEthernet0/0/1]int l0

[r3-LoopBack0]ip add 3.3.3.3 24

[r4]int g0/0/0

[r4-GigabitEthernet0/0/0]ip add 34.1.1.2 24

[r4-GigabitEthernet0/0/0]int g0/0/1

[r4-GigabitEthernet0/0/1]ip add 45.1.1.1 24

[r4-GigabitEthernet0/0/1]int l0

[r4-LoopBack0]ip add 4.4.4.4 24

[r4-LoopBack0]int g0/0/2

[r4-GigabitEthernet0/0/2]ip add 54.1.1.1 24

[r4-GigabitEthernet0/0/2]

[r5]int g0/0/0

[r5-GigabitEthernet0/0/0]ip add 45.1.1.2 24

Error: The address already exists.

[r5-GigabitEthernet0/0/0]int g0/0/1

[r5-GigabitEthernet0/0/1]ip add 54.1.1.2 24

[r5-GigabitEthernet0/0/1]int l0

[r5-LoopBack0]ip add 5.5.5.5 24

[r5-LoopBack1]ip add 99.1.1.1 24

2.写静态使R1、R2之间可通和使R4、R5之间可通。

[r1]ip route-static 2.2.2.2 32 12.1.1.2

[r2]ip route-static 1.1.1.1 32 12.1.1.1

[r4]ip route-static 5.5.5.5 32 45.1.1.2

[r4]ip route-static 5.5.5.5 32 54.1.1.2

[r5]ip route-static 4.4.4.4 32 45.1.1.1

[r5]ip route-static 4.4.4.4 32 54.1.1.1

3.使用OSPF使R2、R3、R4之间可通。

[r2]ospf 1 router-id 2.2.2.2

[r2-ospf-1]a 0.

[r2-ospf-1-area-0.0.0.0]network 2.2.2.2 0.0.0.0

[r2-ospf-1-area-0.0.0.0] network 23.1.1.1 0.0.0.0

[r3]ospf 1 router-id 3.3.3.3

[r3-ospf-1]area 0

[r3-ospf-1-area-0.0.0.0]network 23.1.1.2 0.0.0.0

[r3-ospf-1-area-0.0.0.0]network 3.3.3.3 0.0.0.0

[r4]ospf 1 router-id 4.4.4.4

[r4-ospf-1]a 0

[r4-ospf-1-area-0.0.0.0]network 34.1.1.2 0.0.0.0

[r4-ospf-1-area-0.0.0.0]network 4.4.4.4 0.0.0.0

4.BGP的建邻

外部：

[r1]bgp 1

[r1-bgp]router-id 1.1.1.1

[r1-bgp]peer 2.2.2.2 as-number 2

[r1-bgp]peer 2.2.2.2 connect-interface LoopBack 0
[r1-bgp]peer 2.2.2.2 ebgp-max-hop 2

默认IBGP邻居间数据包的TTL值为255，EBGP邻居间TTL为1；故一旦使用环回建立ebgp邻居关系，必须修改TTL值，否则无法建立

[r2]bgp 2

[r2-bgp]peer 1.1.1.1 as-number 1

[r2-bgp]peer 1.1.1.1 connect-interface LoopBack 0
[r2-bgp]peer 1.1.1.1 ebgp-max-hop 2

[r4-bgp]peer 5.5.5.5 as-number 3

[r4-bgp]peer 5.5.5.5 connect-interface LoopBack 0
[r4-bgp]peer 5.5.5.5 ebgp-max-hop 2

[r5]bgp 3

[r5-bgp]router-id 5.5.5.5

[r5-bgp]peer 4.4.4.4 as-number 2

[r5-bgp]peer 4.4.4.4 connect-interface LoopBack 0
[r5-bgp]peer 4.4.4.4 ebgp-max-hop 2

内部：

本地从一个IBGP邻居处学习到的路由条目，不得传递给本地的其他IBGP邻居；

需要两两建邻

[r2-bgp]peer 3.3.3.3 as-number 2

[r2-bgp]peer 3.3.3.3 connect-interface LoopBack 0

[r2-bgp]peer 3.3.3.3 next-hop-local

[r2-bgp]peer 4.4.4.4 as-number 2

[r2-bgp]peer 4.4.4.4 connect-interface LoopBack 0

[r2-bgp]peer 4.4.4.4 next-hop-local

[r3]bgp 2

[r3-bgp]router-id 3.3.3.3

[r3-bgp]peer 2.2.2.2 as-number 2

[r3-bgp]peer 2.2.2.2 connect-interface LoopBack 0

[r3-bgp]peer 2. as-number 2

[r3-bgp]peer 4.4.4.4 as-number 2

[r3-bgp]peer 4.4.4.4 connect-interface LoopBack 0

[r3-bgp]peer 4.4.4.4 next-hop-local [r4]bgp 2

[r4-bgp]router-id 4.4.4.4

[r4-bgp]peer 3.3.3.3 as-number 2

[r4-bgp]peer 3.3.3.3 connect-interface LoopBack 0

[r4-bgp]peer 3.3.3.3 next-hop-local

[r4-bgp]peer 2.2.2.2 as-number 2

[r4-bgp]peer 2.2.2.2 connect-interface LoopBack 0

[r4-bgp]peer 2.2.2.2 next-hop-local

5.宣告路由

[r1-bgp]network 1.1.1.0 24

[r2-bgp]network 2.2.2.0 24

[r3-bgp]network 3.3.3.0 24

[r4-bgp]network 4.4.4.0 24

[r5-bgp]network 5.5.5.0 24

[r5-bgp]network 99.1.1.1 24

BGP基础建邻+宣告实验