BGP选路原则详解

单击此处编辑母版标题样式,*,单击此处编辑母版文本样式,单击此处编辑母版文本样式,单击此处编辑母版文本样式,单击此处编辑母版文本样式,Slide Title, 2007 Cisco Systems, Inc. All rights reserved.,Cisco Confidential,Presentation_ID,111,Body Text,Second Level,Third Level,Fourth Level,Fifth Level,BGP,路由选路原则详解,V1.0,学,习总结，个人见解，如有错误欢迎改正！,学习目标,掌握,BGP,十三条选路原则的原理,熟练掌握常见的,BGP,路由选路原则,BGP,路由选路原则,1.Weight,属性,2.Local Preference,属性,3.,本地路由始发方式,4.AS-Path,长度,5.Origin,属性,6.MED,属性,7.EBGP,优于,IBGP,8.,到达,Next-hop,的代价,9.,执行等价负载均衡,10.EBGP,路由接收的顺序,11.,路由的,Router-ID,12.Cluster-list,长度,13.,配置的,BGP Peer,指定地址,第一条,:Weight,属性,比较原则及配置注意事项,:,Cisco,私有,可通过关联,Route-map,方式进行配置,该值无法传递给其他,BGP Peer,只能在本地使用,.,携带的,Weight,值越大,则该路由越优先,.,本地始发路由的默认值是,32768,从其他,BGP Peer,学习过来的路由的默认值是,0,虽然,Weight,属性是,Cisco,私有的,但是很多厂商也是内置该属性,(,但无法显示及修改,),这样就保证了本地始发的路由是最优先的,因为本地始发路由的,”Weight”,为,32768,从其他,BGP Peer,学习过来的路由的,”Weight”,为,0.,第一条,:Weight,属性,实验验证,R2,、,R3,分别通告,10.0.0.0,给,R1,R1,将,10.0.0.0,使用,network,方式引入,BGP,10.0.0.0/8,10.0.0.0/8,10.0.0.0/8,AS 1,AS 2,R3,R1,R2,IBGP,EBGP,第一条,:Weight,属性,实验验证,R1,的,BGP,表,r1#sh ip bgp,BGP table version is 2, local router ID is 9.9.0.1,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,* i10.0.0.0 9.9.13.3 0 100 0 i,* 9.9.12.2 0 0 2 i,* 0.0.0.0 0 32768 i,第一条,:Weight,属性,实验验证,R1,对,BGP Peer,应用不同的,Route-map,修改所学习路由的,Weight,值,10.0.0.0/8,10.0.0.0/8,10.0.0.0/8,AS 1,AS 2,R3,R1,R2,IBGP,EBGP,router bgp 1 -R1,的路由策略,neighbor 9.9.12.2 route-map FROM_R2 in,route-map FROM_R2 permit 10,set weight 65535,第一条,:Weight,属性,实验验证,R1,的,BGP,表选路结果,r1#sh ip bgp,BGP table version is 7, local router ID is 9.9.0.1,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,r i10.0.0.0 9.9.13.3 0 100 0 i,r 9.9.12.2 0 65535 2 i,r 0.0.0.0 0 32768 i,BGP,路由选路原则,1.Weight,属性,2.Local Preference,属性,3.,本地路由始发方式,4.AS-Path,长度,5.Origin,属性,6.MED,属性,7.EBGP,优于,IBGP,8.,到达,Next-hop,的代价,9.,执行等价负载均衡,10.EBGP,路由接收的顺序,11.,路由的,Router-ID,12.Cluster-list,长度,13.,配置的,BGP Peer,指定地址,第二条,:Local Preference,属性,比较原则及配置注意事项,:,值越大,越优先,默认情况下,本地始发的路由的,LP,为,100,从,EBGP Peer,接收的路由的,LP,为,100.,Local Preference,属性只能在,IBGP Peer,之间传递,不能在,EBGP Peer,之间传递,如果在,EBGP Peer,之间收到的路由的路径属性中携带了,Local Preference,则会触发,Notifacation,报文,造成会话中断,第二条,:Local Preference,属性,比较原则及配置注意事项,:,Local Preference,通过如下三种方法进行设置,:,通过将,IGP,路由引入,BGP,时关联,Route-map,进行设置,针对,IBGP Peer,应用,IN/OUT,方向的,Route-map,对从,Peer,接收到的或者通告给,Peer,的所有或部分路由进行设置,针对,EBGP Peer,应用,IN,方向的,Route-map,对从,Peer,接收到的所有或部分路由进行设置,Local Preference,为,BGP,选路策略中经常使用的一个路径属性,第二条,:Local Preference,属性,实验一,:Local Prefenerce,无法在,EBGP Peer,之间传递,R1,R2,AS 1,AS 2,10.0.0.0/8,EBGP,router bgp 2,network 10.0.0.0,neighbor 9.9.12.1 remote-as 1,neighbor 9.9.12.1 route-map TO_R1 out,!,route-map TO_R1 permit 10,set local-preference 500,第二条,:Local Preference,属性,实验一,:Local Prefenerce,无法在,EBGP Peer,之间传递,查看本地始发的,BGP,路由的,LP,值,r2#show ip bgp,BGP table version is 2, local router ID is 9.9.0.2,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,* 10.0.0.0 0.0.0.0 0 32768 i,空值,?,r2#sh ip b 10.0.0.0,BGP routing table entry for 10.0.0.0/8, version 2,Paths: (1 available, best #1, table Default-IP-Routing-Table),Advertised to non peer-group peers:,9.9.12.1,Local,0.0.0.0 from 0.0.0.0 (9.9.0.2),Origin IGP, metric 0,localpref 100, weight 32768, valid, sourced, local, best,第二条,:Local Preference,属性,实验一,:Local Prefenerce,无法在,EBGP Peer,之间传递,R2,通告给,R1,的,BGP,路由是否携带,LP?,r1#sh ip bgp,BGP table version is 2, local router ID is 9.9.0.1,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,* 10.0.0.0 9.9.12.2 0 0 2 i,500,没有传递,?,r2#sh ip bgp neighbors 9.9.12.1 advertised-routes,BGP table version is 2, local router ID is 9.9.0.2,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,* 10.0.0.0 0.0.0.0 0 32768 i,第二条,:Local Preference,属性,实验一,:Local Prefenerce,无法在,EBGP Peer,之间传递,R2,通告给,R1,的,BGP Update,报文,R2,通告的,10.0.0.0/8,前缀的路径属性中不包含,Local Preference,属性,第二条,:Local Preference,属性,实验二,:,修改本地始发路由的默认,LP,值,R1,R2,AS 1,10.0.0.0/8,IBGP,router bgp 1 -R2,的路由策略,bgp default local-preference 500,network 10.0.0.0,neighbor 9.9.12.1 remote-as 1,第二条,:Local Preference,属性,实验二,:,修改本地始发路由的默认,LP,值,r2#sh ip b,BGP table version is 2, local router ID is 10.0.0.1,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,* 10.0.0.0 0.0.0.0 0 32768 i,空值,?,r2#sh ip b 10.0.0.0,BGP routing table entry for 10.0.0.0/8, version 2,Paths: (1 available, best #1, table Default-IP-Routing-Table),Advertised to non peer-group peers:,9.9.12.1,Local,0.0.0.0 from 0.0.0.0 (10.0.0.1),Origin IGP, metric 0, localpref 500, weight 32768, valid, sourced, local, best,第二条,:Local Preference,属性,实验二,:,修改本地始发路由的默认,LP,值,r1#sh ip b,BGP table version is 4, local router ID is 9.9.0.1,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,*i10.0.0.0 9.9.12.2 0 500 0 i,第二条,:Local Preference,属性,实验三,:,将,IGP,中的路由引入,BGP,时关联,Route-map,设置,LP,R1,R2,AS 1,10.0.0.0/8,IBGP,router bgp 1 -R2,的路由策略,network 10.0.0.0 route-map SET_LP,neighbor 9.9.12.1 remote-as 1,!,route-map SET_LP permit 10,set local-preference 400,第二条,:Local Preference,属性,实验三,:,将,IGP,中的路由引入,BGP,时关联,Route-map,设置,LP,r2#sh ip b,BGP table version is 3, local router ID is 10.0.0.1,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,* 10.0.0.0 0.0.0.0 0 400 32768 i,r1#sh ip b,BGP table version is 6, local router ID is 9.9.0.1,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,*i10.0.0.0 9.9.12.2 0 400 0 i,第二条,:Local Preference,属性,实验四,:,对,IBGP Peer,应用,IN/OUT,方向,Route-map,R3,单向访问,R6,的数据流需求,R1R2,对,R3,应用,OUT,方向,Route-map,R1,AS 1,R2,R3,R4,R5,R6,AS 2,以该方式部署策略,对数据流控制的作用范围,10.0.0.0/8,11.0.0.0/8,EBGP,第二条,:Local Preference,属性,实验四,:,对,IBGP Peer,应用,IN/OUT,方向,Route-map,R4,、,R5,正常通告,R6,的路由，,R1,、,R2,的,BGP,表,R1,AS 1,R2,R3,R4,R5,R6,AS 2,10.0.0.0/8,11.0.0.0/8,EBGP,r1#sh ip bgp,Network Next Hop Metric LocPrf Weight Path,* 10.0.0.0 9.9.15.5 0 2 i,* 9.9.14.4 0 2 i,* 11.0.0.0 9.9.15.5 0 2 i,* 9.9.14.4 0 2 i,r2#sh ip bgp,Network Next Hop Metric LocPrf Weight Path,* 10.0.0.0 9.9.25.5 0 2 i,* 9.9.24.4 0 2 i,* 11.0.0 9.9.25.5 0 2 i,* 9.9.24.4 0 2 i,IBGP,IBGP,IBGP,IBGP,第二条,:Local Preference,属性,实验四,:,对,IBGP Peer,应用,IN/OUT,方向,Route-map,R1,、,R2,的路由策略,router bgp 1 -R1,的路由策略,neighbor 9.9.13.3 route-map TO_R3 out,access-list 1 permit 10.0.0.0,access-list 2 permit 11.0.0.0,route-map TO_R3 permit 10,match ip address 1,set local-preference 500,route-map TO_R3 permit 20,match ip address 2,set local-preference 400,router bgp 1 -R2,的路由策略,neighbor 9.9.23.3 route-map TO_R3 out,access-list 1 permit 10.0.0.0,access-list 2 permit 11.0.0.0,route-map TO_R3 permit 10,match ip address 1,set local-preference 400,route-map TO_R3 permit 20,match ip address 2,set local-preference 500,R1,AS 1,R2,R3,R4,R5,R6,AS 2,10.0.0.0/8,11.0.0.0/8,EBGP,IBGP,IBGP,IBGP,IBGP,第二条,:Local Preference,属性,实验四,:,对,IBGP Peer,应用,IN/OUT,方向,Route-map,R3,的路由选路结果,r3#sh ip b,BGP table version is 6, local router ID is 9.9.0.3,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,* i10.0.0.0 9.9.23.2 0 400 0 2 i,*i 9.9.13.1 0 500 0 2 i,*i11.0.0.0 9.9.23.2 0 500 0 2 i,* i 9.9.13.1 0 400 0 2 i,R1,AS 1,R2,R3,R4,R5,R6,AS 2,10.0.0.0/8,11.0.0.0/8,EBGP,IBGP,IBGP,IBGP,IBGP,第二条,:Local Preference,属性,实验四,:,对,IBGP Peer,应用,IN/OUT,方向,Route-map,路由策略结果：,R3,到,R6,的实际单向数据流,R1,AS 1,R2,R3,R4,R5,R6,AS 2,10.0.0.0/8,11.0.0.0/8,EBGP,以该方式部署策略,对数据流控制的作用范围,第二条,:Local Preference,属性,实验五,:,对,EBGP Peer,应用,IN,方向,Route-map,R3,单向访问,R6,的数据流需求,R1R2,分别对,R4R5,应用,OUT,方向的,Route-map,R1,AS 1,R2,R3,R4,R5,R6,AS 2,以该方式部署策略,对数据流控制的作用范围,10.0.0.0/8,11.0.0.0/8,EBGP,第二条,:Local Preference,属性,实验五,:,对,EBGP Peer,应用,IN,方向,Route-map,R1,、,R2,的路由策略,router bgp 1 -R1,的路由策略,neighbor 9.9.14.4 route-map FROM_R4 in,access-list 1 permit 10.0.0.0,route-map FROM_R4 permit 10,match ip address 1,set local-preference 500,route-map FROM_R4 permit 20,router bgp 1 -R2,的路由策略,neighbor 9.9.25.5 route-map FROM_R5 in,access-list 2 permit 11.0.0.0,route-map FROM_R5 permit 10,match ip address 2,set local-preference 500,route-map FROM_R5 permit 20,R1,AS 1,R2,R3,R4,R5,R6,AS 2,10.0.0.0/8,11.0.0.0/8,EBGP,IBGP,IBGP,IBGP,IBGP,第二条,:Local Preference,属性,实验五,:,对,EBGP Peer,应用,IN,方向,Route-map,R1,、,R2,的,BGP,表,r1#sh ip bgp,Network Next Hop Metric LocPrf Weight Path,* 10.0.0.0 9.9.15.5 0 2 i,* 9.9.14.4 500 0 2 i,* 11.0.0.0 9.9.14.4 0 2 i,* 9.9.15.5 0 2 i,r2#sh ip bgp,Network Next Hop Metric LocPrf Weight Path,* 10.0.0.0 9.9.25.5 0 2 i,* 9.9.24.4 0 2 i,* 11.0.0.0 9.9.25.5 500 0 2 i,* 9.9.24.4 0 2 i,R1,AS 1,R2,R3,R4,R5,R6,AS 2,10.0.0.0/8,11.0.0.0/8,EBGP,IBGP,IBGP,IBGP,IBGP,第二条,:Local Preference,属性,实验五,:,对,EBGP Peer,应用,IN,方向,Route-map,R3,的,BGP,表,r3#sh ip bgp,BGP table version is 10, local router ID is 9.9.0.3,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,* i10.0.0.0 9.9.23.2 0 100 0 2 i,*i 9.9.13.1 0 500 0 2 i,*i11.0.0.0 9.9.23.2 0 500 0 2 i,* i 9.9.13.1 0 100 0 2 i,R1,AS 1,R2,R3,R4,R5,R6,AS 2,10.0.0.0/8,11.0.0.0/8,EBGP,IBGP,IBGP,IBGP,IBGP,第二条,:Local Preference,属性,实验五,:,对,EBGP Peer,应用,IN,方向,Route-map,路由策略结果：,R3,到,R6,的实际单向数据流,R1,AS 1,R2,R3,R4,R5,R6,AS 2,10.0.0.0/8,11.0.0.0/8,以该方式部署策略,对数据流控制的作用范围,BGP,路由选路原则,1.Weight,属性,2.Local Preference,属性,3.,本地路由始发方式,4.AS-Path,长度,5.Origin,属性,6.MED,属性,7.EBGP,优于,IBGP,8.,到达,Next-hop,的代价,9.,执行等价负载均衡,10.EBGP,路由接收的顺序,11.,路由的,Router-ID,12.Cluster-list,长度,13.,配置的,BGP Peer,指定地址,第三条,:,本地路由始发方式,比较原则及配置注意事项,该比较原则主要是指本地在进入一条,IGP,路由进去,BGP,表时，使用不同的方式比如,network,或,redistribute,等，那么这些方式之间是存在优先顺序的：,networkredistributeaggregate,注意，该原则是不会作为,BGP,路由选路策略的,第三条,:,本地路由始发方式,实验验证,本地分别以,3,种方式引入一条路由，如下配置所示,interface Loopback1,ip address 3.3.3.3 255.255.255.255,router bgp 1,network 3.3.3.3 mask 255.255.255.255 route-map A,aggregate-address 3.3.3.3 255.255.255.255 attribute-map C,redistribute connected route-map B,route-map A permit 10,set local-preference 200,route-map B permit 10,set local-preference 300,route-map C permit 10,set local-preference 400,第三条,:,本地路由始发方式,实验验证,本地,BGP,表中的显示，,network,方式为第一选择,r3#sh ip bgp,BGP table version is 13, local router ID is 9.9.0.3,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,* 3.3.3.3/32 0.0.0.0 0 200 32768 i,第三条,:,本地路由始发方式,实验验证,将,network 3.3.3.3 mask 255.255.255.255,删除,redistribute,方式成为优选,r3#sh ip b,BGP table version is 14, local router ID is 9.9.0.3,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,* 3.3.3.3/32 0.0.0.0 0 300 32768 ?,BGP,路由选路原则,1.Weight,属性,2.Local Preference,属性,3.,本地路由始发方式,4.AS-Path,长度,5.Origin,属性,6.MED,属性,7.EBGP,优于,IBGP,8.,到达,Next-hop,的代价,9.,执行等价负载均衡,10.EBGP,路由接收的顺序,11.,路由的,Router-ID,12.Cluster-list,长度,13.,配置的,BGP Peer,指定地址,第四条,:AS-Path,长度,比较原则及配置注意事项,优选长度小的,AS-Path,列表,其他,AS-Path,比较原则：,在做聚合路由时，使用,as-set,后产生的,AS-Path,列表中的,里的,AS,号长度只算一个,AS,号的长度,在联盟内的,AS-Path,列表中的,(),的,AS,号长度不做计算依据,当向,EBGP Peer,通告路由时，将自己的,AS,号加在,AS-Path,列表的最左端，向,IBGP Peer,通告路由时，不会对,AS-Path,列表做任何修改,第四条,:AS-Path,长度,比较原则及配置注意事项,修改,AS-Path,列表的方法：,可以通过对,EBGP Peer,使用,IN/OUT,方向的,Route-map,，使用,set as-path prepend,命令来添加,AS,号。,注意，上述操作只能对,EBGP Peer,，对,IBGP Peer,无法生效。,可以在,BGP,进程下使用,bgp bestpath as-path ignore,命令来跳过,AS-Path,的长度比较,修改,AS-Path,长度可作为,BGP,选路策略的一种。,第四条,:AS-Path,长度,实验一：使用,OUT,方向的,Route-map,来修改,AS-Path,R3,访问,R4,的单向数据流需求,R1,R2,R3,R4,AS1,AS2,10.0.0.0/8,以该方式部署策略,对数据流控制的作用范围,第四条,:AS-Path,长度,实验一：使用,OUT,方向的,Route-map,来修改,AS-Path,R1,、,R2,的路由策略,(R1,保持默认,),router bgp 2 -R2,的路由策略,neighbor 9.9.23.3 route-map TO_R3 out,route-map TO_R3 permit 10,set as-path prepend 5 5 5,R1,R2,R3,R4,AS1,AS2,10.0.0.0/8,IBGP,EBGP,EBGP,IBGP,第四条,:AS-Path,长度,实验一：使用,OUT,方向的,Route-map,来修改,AS-Path,R3,的,BGP,表选路结果,r3#sh ip b,BGP table version is 2, local router ID is 9.9.0.3,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,* 10.0.0.0 9.9.23.2 0,2,5 5 5,i,* 9.9.13.1 0 2 i,第四条,:AS-Path,长度,实验二：使用,IN,方向的,Route-map,来修改,AS-Path,R3,访问,R4,的单向数据流需求,R1,R2,R3,R4,AS1,AS2,10.0.0.0/8,以该方式部署策略,对数据流控制的作用范围,第四条,:AS-Path,长度,实验二：使用,IN,方向的,Route-map,来修改,AS-Path,R3,的路由策略,router bgp 1 -R3,的路由策略,neighbor 9.9.23.2 route-map FROM_R2 in,route-map FROM_R2 permit 10,set as-path prepend 5 5 5,R1,R2,R3,R4,AS1,AS2,10.0.0.0/8,IBGP,EBGP,EBGP,IBGP,第四条,:AS-Path,长度,实验二：使用,IN,方向的,Route-map,来修改,AS-Path,R3,的,BGP,表选路结果,r3#sh ip bgp,BGP table version is 2, local router ID is 9.9.0.3,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,* 10.0.0.0 9.9.23.2 0,5 5 5,2 i,* 9.9.13.1 0 2 i,不同方向的,route-map,对于插入的,AS,号的位置是不同的,BGP,路由选路原则,1.Weight,属性,2.Local Preference,属性,3.,本地路由始发方式,4.AS-Path,长度,5.Origin,属性,6.MED,属性,7.EBGP,优于,IBGP,8.,到达,Next-hop,的代价,9.,执行等价负载均衡,10.EBGP,路由接收的顺序,11.,路由的,Router-ID,12.Cluster-list,长度,13.,配置的,BGP Peer,指定地址,第五条,:Origin,属性,比较原则及配置注意事项,三种不同的,Origin,属性的优先顺序,:IGPEGPincomplete,Origin,属性会一直在,BGP,路由中携带,Origin,属性配置方法：,将,IGP,路由引入,BGP,时关联,Route-map,进行设置,默认情况下，,network,方式产生的,BGP,路由的,Origin,属性为,IGP,，而,redistribute,方式产生的,BGP,路由的,Origin,属性为“？”,对,BGP Peer,应用,IN/OUT,方向的,Route-map,进行设置,很少使用设置,Origin,属性作为,BGP,路由选路策略,第五条,:Origin,属性,实验,1,：设置,Origin,属性,R1R2R3,分别以,network,方式引入路由，,R1R3,关联不同的,Route-map,设置不同的,Origin,属性,11.0.0.0/8,13.0.0.0/8,12.0.0.0/8,AS 1,AS 2,R3,R1,R2,IBGP,EBGP,router bgp 1 -R3,的路由策略,network 13.0.0.0 route-map SET_Origin,route-map SET_Origin permit 10,set origin incomplete,router bgp 1 -R1,的路由策略,network 11.0.0.0 route-map SET_Origin,route-map SET_Origin permit 10,set origin egp,第五条,:Origin,属性,实验,1,：设置,Origin,属性,R1,的,BGP,表,r1# sh ip bgp,BGP table version is 4, local router ID is 9.9.0.1,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,* 11.0.0.0 0.0.0.0 0 32768 e,* 12.0.0.0 9.9.12.2 0 0 2 i,*i13.0.0.0 9.9.13.3 0 100 0 ?,第五条,:Origin,属性,实验,1,：设置,Origin,属性,R1,对,R3,应用,IN,方向的,Route-map,修改,Origin,属性，,R2,对,R1,使用,OUT,方向的,Route-map,修改,Origin,属性,11.0.0.0/8,13.0.0.0/8,12.0.0.0/8,AS 1,AS 2,R3,R1,R2,IBGP,EBGP,router bgp 1 -R1,的路由策略,neighbor 9.9.13.3 route-map FROM_R3 in,route-map FROM_R3 permit 10,set origin igp,router bgp 2 -R2,的路由策略,neighbor 9.9.12.1 route-map TO_R1 out,route-map TO_R1 permit 10,set origin incomplete,第五条,:Origin,属性,实验,1,：设置,Origin,属性,R1,的,BGP,表,r1#sh ip bgp,BGP table version is 6, local router ID is 9.9.0.1,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,* 11.0.0.0 0.0.0.0 0 32768 e,* 12.0.0.0 9.9.12.2 0 0 2 ?,*i13.0.0.0 9.9.13.3 0 100 0 i,第五条,:Origin,属性,实验,2,：不同,Origin,属性之间的优先顺序,10.0.0.0/8,10.0.0.0/8,AS 1,R3,R1,R2,IBGP,IBGP,10.0.0.0/8,R4,IBGP,router bgp 1 -R3,的路由策略,network 10.0.0.0 route-map SET_Origin,route-map SET_Origin permit 10,set origin incomplete,R2,仅使用,network,方式引入,10.0.0.0,router bgp 1 -