1、BGP 路由反射器实验 2009-09-04 09:15:43标签：cisco 路由 bgp 反射器 原创作品，允许转载，转载时请务必以超链接形式标明文章 原始出处 、作者信息和本声明。否则将追究法律责任。http:/ BGP 路由反射器实验报告一、 实验目的配置 IBGP 路由器使用路由反射器和简单的路由过滤器二、 拓扑结构图三、 实验步骤1. 配置基本接口地址(略)测试: sanjose3(config)#do ping 192.168.1.5 sanjose3(config)#do ping 172.24.1.18 通 基本地址配置成功2. 配置内部 IBGP 协议采用 ripSanjo
2、se3(config-if)#router ripSanjose3(config-router)#net 192.168.1.0Sanjose3(config-router)#net 172.24.0.0sanjose1(config-if)#router ripsanjose1(config-router)#net 192.168.1.0sanjose2(config-if)#router ripsanjose2 (config-router)#net 172.24.0.03. 配置 bgp 协议sanjose3(config)#router bgp 100sanjose3(config-r
3、outer)#neigh 192.168.1.5 remote-as 100sanjose3(config-router)#neigh 172.24.1.18 remote-as 100 sanjose3(config-router)#net 200.100.50.0sanjose1(config)#router bgp 100sanjose1(config-router)#neigh 192.168.1.6 remote-as 100sanjose2(config)#router bgp 100sanjose2(config-router)#neigh 172.24.1.17 remote-
4、as 100sanjose2(config-router)#net 199.9.9.0查看结果:sanjose2#sh ip bgpNetwork Next Hop Metric LocPrf Weight Path* 199.9.9.0 0.0.0.0 0 32768 iri200.100.50.0 172.24.1.17 0 100 0 isanjose3#sh ip bgpNetwork Next Hop Metric LocPrf Weight Pathri199.9.9.0 172.24.1.18 0 100 0 isanjose1#sh ip bgpNetwork Next Hop
5、 Metric LocPrf Weight Pathri200.100.50.0 192.168.1.6 0 100 0 isanjose1#show ip routeR 200.100.50.0/24 120/1 via 192.168.1.6, 00:00:11, Serial0/0R 172.24.0.0/16 120/1 via 192.168.1.6, 00:00:11, Serial0/0192.168.1.0/30 is subnetted, 1 subnetsC 192.168.1.4 is directly connected, Serial0/0问题:为什么在 sanjos
6、e1 上看不到哦啊 199.9.9.0 网络的 bgp 条目原因:因为在一个自治系统内,由于水平分割的原则, 通过 IBGP 学习到的路径从来不会公告给其他 IBGP4. 配置路由反射器打破水平分割sanjose3(config)#router bgp 100sanjose3(config-router)#neigh 192.168.1.5 route-reflector-client sanjose3(config-router)#neigh 172.24.1.18 route-reflector-clientsanjose1#sh ip bgpNetwork Next Hop Metric
7、 LocPrf Weight Path*i199.9.9.0 172.24.1.18 0 100 0 i*i200.100.50.0 192.168.1.6 0 100 0 isanjose1#sh ip routeB 199.9.9.0/24 200/0 via 172.24.1.18, 00:00:52B 200.100.50.0/24 200/0 via 192.168.1.6, 00:01:48R 172.24.0.0/16 120/1 via 192.168.1.6, 00:00:14, Serial0/0192.168.1.0/30 is subnetted, 1 subnetsC
8、 192.168.1.4 is directly connected, Serial0/0测试: sanjose1#ping 199.9.9.1 通sanjose3#sh ip proRouting Protocol is “bgp 100“Outgoing update filter list for all interfaces is not setIncoming update filter list for all interfaces is not setRoute Reflector for address family IPv4 Unicast, 2 clientsRoute R
9、eflector for address family VPNv4 Unicast, 2 clientsRoute Reflector for address family IPv4 Multicast, 2 clientsIGP synchronization is disabledAutomatic route summarization is disabledNeighbor(s):Address FiltIn FiltOut DistIn DistOut Weight RouteMap172.24.1.18 192.168.1.5 Maximum path: 1Routing Info
10、rmation Sources:Gateway Distance Last Update172.24.1.18 200 00:03:07Distance: external 20 internal 200 local 2005. 配置汇总地址sanjose2(config)#router bgp 100sanjose2(config-router)#aggresanjose2(config-router)#aggregate-address 199.0.0.0 255.255.255.0sanjose2#sho ip bgp 199.0.0.0BGP routing table entry f
11、or 199.0.0.0/8, version 8Paths: (1 available, best #1, table Default-IP-Routing-Table)Flag: 0x820Advertised to update-groups:1 Local, (aggregated by 100 199.9.9.1)0.0.0.0 from 0.0.0.0 (199.9.9.1)Origin IGP, localpref 100, weight 32768, valid, aggregated, local, atomic-aggregate, bestsanjose1#show ip
12、 routeB 199.9.9.0/24 200/0 via 172.24.1.18, 00:11:04B 200.100.50.0/24 200/0 via 192.168.1.6, 00:12:00R 172.24.0.0/16 120/1 via 192.168.1.6, 00:00:09, Serial0/0192.168.1.0/30 is subnetted, 1 subnetsC 192.168.1.4 is directly connected, Serial0/0B 199.0.0.0/8 200/0 via 172.24.1.18, 00:02:41 6. 配置路由过滤防止
13、 sanjose3 发送 199.9.9.0/24 给其他网络sanjose3(config)#ip prefix-list supernetonly permit 199.0.0.0/8sanjose3(config)#router bgp 100sanjose3(config-router)#neighbor 192.168.1.5 prefix-list supernetonly out 查看结果sanjose1#show ip routeR 172.24.0.0/16 120/1 via 192.168.1.6, 00:00:23, Serial0/0192.168.1.0/30 is subnetted, 1 subnetsC 192.168.1.4 is directly connected, Serial0/0B 199.0.0.0/8 200/0 via 172.24.1.18, 00:05:39只有一条 bgp 的汇总条目!
