eigrp默认路由总结.doc

拓扑R1（s1/2）-(s1/3) R2 (s1/2)-(s1/3) R31：写一条默认路由，network到EIGRP进程ip route interface (接口必须是up而且要有address，或者是null0,也可以是lookback接口)router eigrp ASnetwork 缺点:会在宣告的路由器上,将所有接口激活.包括你不想激活的接口注意在RIP中创建的默认路由不会从所跟的接口和能到达下跳地址的接口传递出去但是EIGRP可以这个是因为水平分割在RIP中是默认关闭的而EIGRP不是。R2(config)#ip route null 0R2(config)#router eigrp 1R2(config-router)#network 2：写一条默认路由，重分布静态到EIGRP进程ip route interface(下一跳可以是出口标识，也可以是下一跳ip地址。接口必须是up而且要有address或者是null0)router eirp ASredistribute static metric 10000 100 255 1 1500默认路由出现的形式D*EX,AD=170和RIP的对比和第1种方法一样。R2(config)#ip route null 0R2(config)#router eigrp 1R2(config-router)#redistribute static metric 10000 100 255 1 15003 汇总一条 的路由，本地会产生一条null0的的路由接口下手工汇总 ip summary-address eirp 90 ,在连接eigrp内部router的接口上汇总的默认路由会传递给接口连接的邻居(不在乎auto/no auto-summary/也不需要写静态)缺点:具有方向性.具有抑制明细的特点。当RIP时必须创建默认路由,才能传播进去ip summary-address eigrp 1 明细路由被抑制了4、ip default-network x.x.x.x(必须主类的网络)在边界路由器上，使用全局配置命令ip default-network network-number，将network-number配置成默认网络。在EIGRP进程下使用network将其通告给其它路由器，使得其它路由器将该网络作为其默认网络。ip Default-network 的作用是把缺省路由通过路由协议(eigrp)广播给内网路由器。注意：x.x.x.x必须主类的网络如果将学到路由当作传递的缺省网络.此时路由条目必须是主类，因此需要作auto-summary或者手工汇总EIGRP不会产生的默生路由，而是借用带有D*的路由的下一跳做为缺省下一跳。RIP传递是一条/0的默认路由。三部曲：（1）R2(config)#ip route null 0写一条静态路由（下一跳最好写出接口或者null 0，不要写地址，写地址可能会出错）（2）R2config)#ip default-network 写default network（3）R2(config)#router eigrp 1network一下R2(config-router)#net 在EIGRP中可以通过no default-information in/out来控制默认路由的发布default-information 不是用来传递默认路由而是用来控制（但是RIP是）default-information allow in 是默认在进程中开启,允许所有可传递的默认网络进入本路由器default-information allow out 是默认在进程中开启,允许所有可传递的默认网络传递出本路由器no default-information in/out:表示不允许进入默认路由或者传递默认路由，而不是no掉这条命令R3(config-router)#default-information allowed in，需要重置邻居关系后才会生效没有了默认路由在中小型企业中，一般会考虑内网所有的电脑通过一台边界路由器（即公司与外网相连的那台路由器）来进行网上冲浪或是其它internet活动。示例的拓扑图如下：公司的三个点，内部路由器之间通过EIGRP共享路由信息。同时，R2为公司总部的路由器，所有R1和R3的用户都要通过R1来连接internet。只有R2配有一个公网IP：0.目的：要使所有内网之间可以互相通讯，并可以通过R2路由器与外部通讯。本例中假如外部IP：00与00.首先：我们在公司之间配置EIGRP，并通告所有的网段。这个没有问题，经过配置之后，使内部网段之间可以互访。R1中，我们可以使用EIGRP来通告网段：/24 /30 /30，并将Fa1/0配置为被动接口。R2中，通告网段/24 /24 /24及网段0。R3中，通告网段/30 /30 /24,并钭Fa1/0配置为被动接口。经过以上配置，主机之间互ping应该都可以通，同时，C1、C2、C3都可以ping通0/24这个公网IP。由于R2通告了、24网段，三台主机也可ping通0/24。但此时，并不能说明所有的内网主机可以通过R2上网。于是，我们可以在R2上做个默认路由。ip route .0 s2/0则此时：C2可以ping通外网了。VPCS2 ping 0000 icmp_seq=1 ttl=254 time=52.000 ms00 icmp_seq=2 ttl=254 time=30.000 ms00 icmp_seq=3 ttl=254 time=10.000 ms00 icmp_seq=4 ttl=254 time=15.000 ms00 icmp_seq=5 ttl=254 time=81.000 msVPCS2 ping 0000 icmp_seq=1 ttl=254 time=45.000 ms00 icmp_seq=2 ttl=254 time=19.000 ms00 icmp_seq=3 ttl=254 time=34.000 ms00 icmp_seq=4 ttl=254 time=16.000 ms00 icmp_seq=5 ttl=254 time=21.000 ms可以查看R2的路由表：R2#show ip routeCodes: C - connected, S - static, 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 i - IS-IS, su - IS-IS summary, 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 routeGateway of last resort is to network /30 is subnetted, 3 subnetsD 90/2681856 via , 00:41:28, Serial2/1 90/2681856 via , 00:41:28, Serial2/0C is directly connected, Serial2/0C is directly connected, Serial2/1 /24 is subnetted, 3 subnetsD 90/2172416 via , 00:41:28, Serial2/0C is directly connected, FastEthernet0/0D 90/2172416 via , 00:22:19, Serial2/1C /24 is directly connected, Serial2/2S* /0 is directly connected, Serial2/2由于C2与R2直连，经过配置默认路由，则C2网段的电脑可以上外网。但此时，在C1和C3网段上，试着ping外网。C1上：VPCS1 ping 0000 icmp_seq=1 timeout00 icmp_seq=2 timeout00 icmp_seq=3 timeout00 icmp_seq=4 timeout00 icmp_seq=5 timeoutC3上：VPCS3 ping 0000 icmp_seq=1 timeout00 icmp_seq=2 timeout00 icmp_seq=3 timeout00 icmp_seq=4 timeout00 icmp_seq=5 timeout都不通，我们查看R1与R3的路由表：R1：R1#show ip routeCodes: C - connected, S - static, 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 i - IS-IS, su - IS-IS summary, 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 routeGateway of last resort is not set /30 is subnetted, 3 subnetsC is directly connected, Serial0/3C is directly connected, Serial0/0D 90/2681856 via , 00:44:23, Serial0/3 90/2681856 via , 00:44:23, Serial0/0 /24 is subnetted, 3 subnetsC is directly connected, FastEthernet1/0D 90/2172416 via , 00:44:21, Serial0/0D 90/2172416 via , 00:25:13, Serial0/3D /24 90/2681856 via , 00:21:32, Serial0/0R3：R3#show ip routeCodes: C - connected, S - static, 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 i - IS-IS, su - IS-IS summary, 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 routeGateway of last resort is not set /30 is subnetted, 3 subnetsC is directly connected, Serial3/1D 90/2681856 via 0, 00:44:46, Serial3/0 90/2681856 via , 00:44:46, Serial3/1C is directly connected, Serial3/0 /24 is subnetted, 3 subnetsD 90/2172416 via , 00:44:46, Serial3/1D 90/2172416 via 0, 00:44:46, Serial3/0C is directly connected, FastEthernet1/0D /24 90/2681856 via 0, 00:21:57, Serial3/0均没有默认路由，则不在路由表中的目标，数据包则无法到达。在EIGRP中，通告默认路由的方法有两种：第一种是：在边界路由器上声明一条默认路由：ip route interface。然后在EIGRP中，用命令network 来通告它。这样，所有其它邻接路由器将收到默认路由。R2路由器上的配置：router eigrp 100passive-interface FastEthernet0/0network network network network network no auto-summary!ip http server!ip route Serial2/2此时，通告了。刚查看R1与R3的路由表。R1：R1#show ip routeCodes: C - connected, S - static, 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 i - IS-IS, su - IS-IS summary, 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 routeGateway of last resort is to network /30 is subnetted, 3 subnetsC is directly connected, Serial0/3C is directly connected, Serial0/0D 90/2681856 via , 01:04:45, Serial0/3 90/2681856 via , 01:04:45, Serial0/0 /24 is subnetted, 3 subnetsC is directly connected, FastEthernet1/0D 90/2172416 via , 01:04:44, Serial0/0D 90/2172416 via , 00:45:36, Serial0/3D /24 90/2681856 via , 00:41:55, Serial0/0D* /0 90/2681856 via , 00:00:11, Serial0/0R3的路由表：R3#show run*Mar 1 01:08:03.791: %SYS-5-CONFIG_I: Configured from console by consoleR3#show ip routeCodes: C - connected, S - static, 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 i - IS-IS, su - IS-IS summary, 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 routeGateway of last resort is 0 to network /30 is subnetted, 3 subnetsC is directly connected, Serial3/1D 90/2681856 via 0, 01:07:46, Serial3/0 90/2681856 via , 01:07:46, Serial3/1C is directly connected, Serial3/0 /24 is subnetted, 3 subnetsD 90/2172416 via , 01:07:46, Serial3/1D 90/2172416 via 0, 01:07:46, Serial3/0C is directly connected, FastEthernet1/0D /24 90/2681856 via 0, 00:44:57, Serial3/0D* /0 90/2681856 via 0, 00:03:13, Serial3/0从路由表中可以看到，R1、R3都得到了默认路由，并指定出默认路由的出口，这样，所有不在路由表中的目的地，都将经过这些出口转发到R2中，然后R2将它们由出口接口转发到internet上。我们再在C1与C3上ping外网：C1：VPCS1 ping 0000 icmp_seq=1 ttl=253 time=57.000 ms00 icmp_seq=2 ttl=253 time=21.000 ms00 icmp_seq=3 ttl=253 time=30.000 ms00 icmp_seq=4 ttl=253 time=62.000 ms00 icmp_seq=5 ttl=253 time=15.000 msC3：VPCS3 ping 0000 icmp_seq=1 ttl=253 time=52.000 ms00 icmp_seq=2 ttl=253 time=90.000 ms00 icmp_seq=3 ttl=253 time=25.000 ms00 icmp_seq=4 ttl=253 time=49.000 ms00 icmp_seq=5 ttl=253 time=83.000 ms都可以通，这样就达成目的了，不过这样通告路由，外部的EIGRP路由器将会收到EIGRP包。对安全可能会有影响。第二种是：在边界路由器上，使用命令ip default-network +出口的那个网段。来通告此网段作为默认出口。见R2的配置：router eigrp 100passive-interface FastEthernet0/0network network network network no auto-summary!ip http server!ip default-network ip route Serial2/2EIGRP一定要通告，即ip defualt-network通告的这个网段接着，我们再看R1与R3的路由表：R1：R1#show ip routeCodes: C - connected, S - static, 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 i - IS-IS, su - IS-IS summary, 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 routeGateway of last resort is to network /30 is subnetted, 3 subnetsC is directly connected, Serial0/3C is directly connected, Serial0/0D 90/2681856 via , 00:00:49, Serial0/3 90/2681856 via , 00:00:49, Serial0/0 /24 is subnetted, 2 subnetsC is directly connected, FastEthernet1/0D 90/2172416 via , 00:00:48, Serial0/0D* /24 90/2681856 via , 00:00:14, Serial0/0R3：R3#show ip routeCodes: C - connected, S - static, 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 i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2 ia