步骤一:配置三台路由器接口使其连通。
R1的配置
R1(config)# interface Loopback0
R1(config-if)# ip address 1.1.1.1 255.255.255.0
R1(config)# interface Loopback1
R1(config-if)# ip address 2.2.2.2 255.255.255.0
R1(config)# interface s0
R1(config-if)# ip address 10.1.1.1 255.255.255.0
R1(config-if)#no shutdown
R1(config-if)#clock rate 64000
R2的配置
R2(config)#interface Loopback0
R2(config-if)# ip address 3.3.3.3 255.255.255.0
R2(config)#interface Loopback1
R2(config-if)# ip address 4.4.4.4 255.255.255.0
R2(config)#interface Serial0
R2(config-if)# ip address 20.1.1.1 255.255.255.0
R2(config-if)#no shutdown
R2(config)#interface Serial1
R2(config-if)# ip address 10.1.1.2 255.255.255.0
R3的配置
R3(config)#interface Loopback0
R3(config-if)# ip address 5.5.5.5 255.255.255.0
R3(config)#interface Loopback1
R3(config-if)# ip address 6.6.6.6 255.255.255.0
R3(config)#interface Serial1
R3(config-if)# ip address 20.1.1.2 255.255.255.0
R3(config-if)#clockrate 64000
R3(config-if)#no shutdown
步骤二:启用
R1(config)#router eigrp 100 à启用eigrp100
R1(config-router)#network 1.1.1.0 0.0.0.255 à发布相应接口
R1(config-router)#network 10.1.1.0 0.0.0.255
R1(config-router)# no auto-summary à关闭自动汇总
R1(config)#router bgp 65001 à启用BGP65001
R1(config-router)#no synchronization à关闭与IGP的同步
R1(config-router)# network 2.2.2.0 mask 255.255.255.0 à发布参与BGP网段
R1(config-router)# network 10.1.1.0 mask 255.255.255.0
R1(config-router)# neighbor 3.3.3.3 remote-as 65001 à指定邻居
R1(config-router)# neighbor 3.3.3.3 update-source Loopback0 à更新源改为loop0接口
R1(config-router)#no auto-summary à关闭自动汇总
R2(config)#router eigrp 100
R2(config-router)# network 3.3.3.0 0.0.0.255
R2(config-router)# network 10.1.1.0 0.0.0.255
R2(config-router)# no auto-summary
R2(config)#router bgp 65001
R2(config-router)# no synchronization
R2(config-router)# network 4.4.4.0 mask 255.255.255.0
R2(config-router)# network 10.1.1.0 mask 255.255.255.0
R2(config-router)# neighbor 1.1.1.1 remote-as 65001
R2(config-router)# neighbor 1.1.1.1 update-source Loopback0
R2(config-router)# neighbor 1.1.1.1 next-hop-self à将自己指定为邻居的下一跳
R2(config-router)# neighbor 5.5.5.5 remote-as 65002 à指定ebgp邻居
R2(config-router)# neighbor 5.5.5.5 ebgp-multihop 255 à设定多跳,默认为1
R2(config-router)# neighbor 5.5.5.5 update-source Loopback0
R2(config-router)# no auto-summary
R3(config)#router bgp 65002
R3(config-router)#network 6.6.6.0 mask 255.255.255.0
R3(config-router)# neighbor 3.3.3.3 remote-as 65001
R3(config-router)# neighbor 3.3.3.3 ebgp-multihop 255
R3(config-router)# neighbor 3.3.3.3 update-source Loopback0
R3(config-router)# no auto-summary
步骤三:配置静态路由
R2(config)# ip route 5.5.5.0 255.255.255.0 20.1.1.2 à因R2和R3运行在不同的AS,所以要指静态路由来达到可达性
R3(config)# ip route 3.3.3.0 255.255.255.0 20.1.1.1 à同理
步骤四:查看路由表
R1#sh ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
1.0.0.0/24 is subnetted, 1 subnets
C 1.1.1.0 is directly connected, Loopback0
2.0.0.0/24 is subnetted, 1 subnets
C 2.2.2.0 is directly connected, Loopback1
3.0.0.0/24 is subnetted, 1 subnets
D 3.3.3.0 [90/2297856] via 10.1.1.2, 00:09:13, Serial0
4.0.0.0/24 is subnetted, 1 subnets
B 4.4.4.0 [200/0] via 3.3.3.3, 00:07:34 à学来了BGP路由条目
6.0.0.0/24 is subnetted, 1 subnets
B 6.6.6.0 [200/0] via 3.3.3.3, 00:07:34
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.1.0 is directly connected, Serial0
R2#sh ip route
D 1.1.1.0 [90/2297856] via 10.1.1.1, 00:14:09, Serial1
B 2.2.2.0 [200/0] via 1.1.1.1, 00:14:05
C 3.3.3.0 is directly connected, Loopback0
C 4.4.4.0 is directly connected, Loopback1
20.0.0.0/24 is subnetted, 1 subnets
C 20.1.1.0 is directly connected, Serial0
5.0.0.0/24 is subnetted, 1 subnets
S 5.5.5.0 [1/0] via 20.1.1.2
B 6.6.6.0 [20/0] via 5.5.5.5, 00:18:07
C 10.1.1.0 is directly connected, Serial1
R3#sh ip route
B 2.2.2.0 [20/0] via 3.3.3.3, 00:18:06
S 3.3.3.0 [1/0] via 20.1.1.1
B 4.4.4.0 [20/0] via 3.3.3.3, 00:22:07
C 20.1.1.0 is directly connected, Serial1
C 5.5.5.0 is directly connected, Loopback0
C 6.6.6.0 is directly connected, Loopback1
B 10.1.1.0 [20/0] via 3.3.3.3, 00:22:09
步骤五:查看bgp 概要信息
R1#sh ip bgp summary
BGP router identifier 2.2.2.2, local AS number 65001
Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
3.3.3.3 4 65001 13 12 5 0 0 00:08:23 3
R2#sh ip bgp summary
BGP router identifier 4.4.4.4, local AS number 65001
1.1.1.1 4 65001 18 19 5 0 0 00:14:41 2
5.5.5.5 4 65002 22 23 5 0 0 00:18:42 1
R3#sh ip bgp summary
BGP router identifier 6.6.6.6, local AS number 65002
NeighborV AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
3.3.3.3 4 65001 27 26 5 0 0 00:22:36 3
步骤六:查看bgp邻居
R1#sh ip bgp neighbors
BGP neighbor is 3.3.3.3, remote AS 65001, internal link
BGP version 4, remote router ID 4.4.4.4
BGP state = Established, up for 00:10:41 àIBGP邻居已建立
Last read 00:00:41, hold time is 180, keepalive interval is 60 seconds
R2#sh ip bgp neighbors
BGP neighbor is 1.1.1.1, remote AS 65001, internal link
BGP version 4, remote router ID 2.2.2.2
BGP state = Established, up for 00:15:15 àIBGP邻居已建立
BGP neighbor is 5.5.5.5, remote AS 65002, external link
BGP version 4, remote router ID 6.6.6.6
BGP state = Established, up for 00:19:25 àEBGP邻居已建立
R3#sh ip bgp neighbors
BGP neighbor is 3.3.3.3, remote AS 65001, external link
BGP state = Established, up for 00:22:59 àEBGP邻居已建立
步骤七:查看bgp转发表
R1#sh ip bgp
BGP table version is 5, local router ID is 2.2.2.2
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 2.2.2.0/24 0.0.0.0 0 32768 i
*>i4.4.4.0/24 3.3.3.3 0 100 0 i
*>i6.6.6.0/24 3.3.3.3 0 100 0 65002 i
* i10.1.1.0/24 3.3.3.3 0 100 0 i
*> 0.0.0.0 0 32768 i
R2#sh ip bgp
BGP table version is 5, local router ID is 4.4.4.4
Network Next Hop Metric LocPrf Weight Path
*>i2.2.2.0/24 1.1.1.1 0 100 0 i
*> 4.4.4.0/24 0.0.0.0 0 32768 i
*> 6.6.6.0/24 5.5.5.5 0 0 65002 i
* i10.1.1.0/24 1.1.1.1 0 100 0 i
*> 0.0.0.0 0 32768 i
R3#sh ip bgp
BGP table version is 5, local router ID is 6.6.6.6
*> 2.2.2.0/24 3.3.3.3 0 65001 i
*> 4.4.4.0/24 3.3.3.3 0 0 65001 i
*> 6.6.6.0/24 0.0.0.0 0 32768 i
*> 10.1.1.0/24 3.3.3.3 0 0 65001 i
步骤八:用ping命令测试连通性或用扩展ping命令
R1#ping 6.6.6.6
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 60/60/64 ms
R1#ping 4.4.4.4
Success rate is 100 percent (5/5), round-trip min/avg/max = 32/32/32 ms
R2#ping 2.2.2.2
R3#ping 2.2.2.2
Success rate is 100 percent (5/5), round-trip min/avg/max = 60/60/60 ms
r3#ping 4.4.4.4
步骤九:查看配置
R1#sh run
hostname R1
!
interface Loopback0
ip address 1.1.1.1 255.255.255.0
interface Loopback1
ip address 2.2.2.2 255.255.255.0
interface Serial0
ip address 10.1.1.1 255.255.255.0
clockrate 64000
router eigrp 100
network 1.1.1.0 0.0.0.255
network 10.1.1.0 0.0.0.255
no auto-summary
router bgp 65001
no synchronization
network 2.2.2.0 mask 255.255.255.0
network 10.1.1.0 mask 255.255.255.0
neighbor 3.3.3.3 remote-as 65001
neighbor 3.3.3.3 update-source Loopback0
end
R2#sh run
hostname R2
ip address 3.3.3.3 255.255.255.0
ip address 4.4.4.4 255.255.255.0
ip address 20.1.1.1 255.255.255.0
interface Serial1
ip address 10.1.1.2 255.255.255.0
network 3.3.3.0 0.0.0.255
network 4.4.4.0 mask 255.255.255.0
neighbor 1.1.1.1 remote-as 65001
neighbor 1.1.1.1 update-source Loopback0
neighbor 1.1.1.1 next-hop-self
neighbor 5.5.5.5 remote-as 65002
neighbor 5.5.5.5 ebgp-multihop 255
neighbor 5.5.5.5 update-source Loopback0
ip route 5.5.5.0 255.255.255.0 20.1.1.2
!
R3#sh run
Hostname R3
ip address 5.5.5.5 255.255.255.0
ip address 6.6.6.6 255.255.255.0
ip address 20.1.1.2 255.255.255.0
router bgp 65002
network 6.6.6.0 mask 255.255.255.0
neighbor 3.3.3.3 ebgp-multihop 255
ip route 3.3.3.0 255.255.255.0 20.1.1.1
本文转自hexianguo 51CTO博客,原文链接:http://blog.51cto.com/xghe110/89139,如需转载请自行联系原作者