BGP综合实验

在上一个IGP中做下边的实验。

实验要求：

1、EBGP：R3---R2  R4---R3  R2---R1

2、IBGP：R2---R4  R4---R5  R2---R5

3、 所有BGP 邻居关系建立都使用LO0 做更新源（R2—R1 除外） 。使用X。X。X。

X 作为router-id

4、R3 公告lo20:200.200.1.0/24，R5 学习这条路由要优选R2。

5、R5 公告lo20:200.200.5.0/24，AS200的管理员希望AS100 优选来自R2 的路由访问

此目的网络。

6、R1 公告lo20:200.200.4.0/24，这条路由只能在AS200 内传递。

实验拓扑：

配置要点

R1：router bgp 400

 no synchronization

 bgp log-neighbor-changes

 network 200.200.4.0

 neighbor 12.1.1.2 remote-as 200

 no auto-summary

R2：router bgp 200

 no synchronization

 bgp log-neighbor-changes

 neighbor 3.3.3.3 remote-as 100

 neighbor 3.3.3.3 ebgp-multihop 10

 neighbor 3.3.3.3 update-source Loopback10

 neighbor 3.3.3.3 route-map A out

 neighbor 5.5.5.5 remote-as 200

 neighbor 5.5.5.5 update-source Loopback10

 neighbor 5.5.5.5 next-hop-self

 neighbor 12.1.1.1 remote-as 400

 no auto-summary

ip proute-map A deny 10

 match ip address prefix-list A

route-map A permit 20refix-list A seq 5 permit 200.200.4.0/24

R3：router bgp 100

 no synchronization

 bgp log-neighbor-changes

 network 200.200.1.0

 neighbor 2.2.2.2 remote-as 200

 neighbor 2.2.2.2 ebgp-multihop 10

 neighbor 2.2.2.2 update-source Loopback10

 neighbor 4.4.4.4 remote-as 200

 neighbor 4.4.4.4 ebgp-multihop 10

 neighbor 4.4.4.4 update-source Loopback10

 no auto-summary

R4:router bgp 200

 no synchronization

 bgp log-neighbor-changes

 neighbor 3.3.3.3 remote-as 100

 neighbor 3.3.3.3 ebgp-multihop 10

 neighbor 3.3.3.3 update-source Loopback10

 neighbor 5.5.5.5 remote-as 200

 neighbor 5.5.5.5 update-source Loopback10

 neighbor 5.5.5.5 next-hop-self

 no auto-summary

R5：router bgp 200

 no synchronization

 bgp log-neighbor-changes

 network 200.200.5.0

 neighbor 2.2.2.2 remote-as 200

 neighbor 2.2.2.2 update-source Loopback10

 neighbor 2.2.2.2 next-hop-self

 neighbor 4.4.4.4 remote-as 200

 neighbor 4.4.4.4 update-source Loopback10

 no auto-summary

测试：

分别查看R3和R5的BGP表：

R5#show ip bgp

BGP table version is 6, local router ID is 5.5.5.5

Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,

              r RIB-failure, S Stale

Origin codes: i - IGP, e - EGP, ? - incomplete

   Network          Next Hop            Metric LocPrf Weight Path

*>i200.200.1.0      2.2.2.2                  0    100      0 100 i

* i                 4.4.4.4                  0    100      0 100 i

*>i200.200.4.0      2.2.2.2                  0    100      0 400 i

*> 200.200.5.0      0.0.0.0                  0         32768 i

R3# show ip bgp

BGP table version is 11, local router ID is 3.3.3.3

Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,

              r RIB-failure, S Stale

Origin codes: i - IGP, e - EGP, ? - incomplete

   Network          Next Hop            Metric LocPrf Weight Path

*> 200.200.1.0      0.0.0.0                  0         32768 i

*> 200.200.5.0      2.2.2.2                                0 200 i

*                   4.4.4.4                                0 200 i

看下R5的路由表：

R5#show ip route

B    200.200.4.0/24 [200/0] via 2.2.2.2, 00:21:33

     34.0.0.0/8 is variably subnetted, 2 subnets, 2 masks

D EX    34.1.1.3/32 [170/1657856] via 45.1.1.4, 01:33:48, Serial1/0

                    [170/1657856] via 54.1.1.4, 01:33:48, FastEthernet0/0

D EX    34.1.1.0/24 [170/1657856] via 45.1.1.4, 01:33:48, Serial1/0

                    [170/1657856] via 54.1.1.4, 01:33:48, FastEthernet0/0

C    200.200.5.0/24 is directly connected, Loopback20

     2.0.0.0/24 is subnetted, 4 subnets

D EX    2.2.1.0 [170/1657856] via 45.1.1.4, 01:33:32, Serial1/0

                [170/1657856] via 54.1.1.4, 01:33:32, FastEthernet0/0

D EX    2.2.2.0 [170/1657856] via 45.1.1.4, 01:33:32, Serial1/0

                [170/1657856] via 54.1.1.4, 01:33:32, FastEthernet0/0

D EX    2.2.3.0 [170/1657856] via 45.1.1.4, 01:33:32, Serial1/0

                [170/1657856] via 54.1.1.4, 01:33:32, FastEthernet0/0

D EX    2.2.4.0 [170/1657856] via 45.1.1.4, 01:33:33, Serial1/0

                [170/1657856] via 54.1.1.4, 01:33:33, FastEthernet0/0

     3.0.0.0/32 is subnetted, 1 subnets

D EX    3.3.3.3 [170/1657856] via 45.1.1.4, 01:33:33, Serial1/0

                [170/1657856] via 54.1.1.4, 01:33:33, FastEthernet0/0

     4.0.0.0/24 is subnetted, 1 subnets

D EX    4.4.4.0 [170/1657856] via 45.1.1.4, 03:07:09, Serial1/0

                [170/1657856] via 54.1.1.4, 03:07:09, FastEthernet0/0

     5.0.0.0/24 is subnetted, 1 subnets

C       5.5.5.0 is directly connected, Loopback10

B    200.200.1.0/24 [200/0] via 2.2.2.2, 00:21:33

     54.0.0.0/24 is subnetted, 1 subnets

C       54.1.1.0 is directly connected, FastEthernet0/0

     23.0.0.0/24 is subnetted, 1 subnets

D EX    23.1.1.0 [170/1657856] via 45.1.1.4, 01:33:33, Serial1/0

                 [170/1657856] via 54.1.1.4, 01:33:33, FastEthernet0/0

     12.0.0.0/24 is subnetted, 1 subnets

D EX    12.1.1.0 [170/1657856] via 45.1.1.4, 01:33:33, Serial1/0

                 [170/1657856] via 54.1.1.4, 01:33:33, FastEthernet0/0

     45.0.0.0/24 is subnetted, 1 subnets

C       45.1.1.0 is directly connected, Serial1/0

虽然路由表以及BGP表都可以看到路由，但是相互间依然PING不通，IGP中根本没有路由。

R5#ping 200.200.1.3

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 200.200.1.3, timeout is 2 seconds:

!!!!!

Success rate is 100 percent (5/5), round-trip min/avg/max = 212/277/344 ms

R5#ping 200.200.4.1 source 200.200.5.5

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 200.200.4.1, timeout is 2 seconds:

Packet sent with a source address of 200.200.5.5

.....

Success rate is 0 percent (0/5)

看R1路由表：

R1#show ip route

C    200.200.4.0/24 is directly connected, Loopback20

     1.0.0.0/24 is subnetted, 6 subnets

C       1.1.1.0 is directly connected, Loopback10

C       1.1.2.0 is directly connected, Loopback1

C       1.1.3.0 is directly connected, Loopback2

C       1.1.4.0 is directly connected, Loopback3

C       1.1.11.0 is directly connected, Loopback11

C       1.1.22.0 is directly connected, Loopback12

B    200.200.5.0/24 [20/0] via 12.1.1.2, 00:27:50

B    200.200.1.0/24 [20/0] via 12.1.1.2, 00:39:12

     11.0.0.0/24 is subnetted, 1 subnets

C       11.11.11.0 is directly connected, Loopback0

     12.0.0.0/24 is subnetted, 1 subnets

C       12.1.1.0 is directly connected, Serial1/1

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