EIGRP不等价负载均衡

不等价负载简单介绍：所谓不等价负载均衡指的是，到达目的地有多条路径，但是每条路径开销都不一样。并且能够保证在eigrp拓扑表中有路由条目。在路由表中只出现最有条目。
简单实验：实验拓扑图



实验简单配置过程。一、在实验之前，先把拓扑图搭建完成；基本链路联通。下面是基本配置。R1：interface Loopback0 ip address 172.16.11.1 255.255.255.0interface Serial0/0 ip address 172.16.13.1 255.255.255.0 delay 100000 clock rate 64000interface Serial0/1 ip address 172.16.12.1 255.255.255.0 clock rate 64000R2：interface Serial0/0 ip address 172.16.23.2 255.255.255.0 clock rate 64000interface Serial0/1 ip address 172.16.12.2 255.255.255.0 clock rate 64000R3：interface Loopback0 ip address 172.16.33.1 255.255.255.0interface Serial0/0 ip address 172.16.13.3 255.255.255.0 delay 100000 clock rate 64000interface Serial0/1 ip address 172.16.23.3 255.255.255.0 clock rate 64000二、接着在每台路由器上启用EIGRP协议。R1：router eigrp 110 network 172.16.11.0 0.0.0.255 network 172.16.12.0 0.0.0.255 network 172.16.13.0 0.0.0.255 no auto-summary-----在通告网段之前，先把自动汇总关闭。默认情况下，自动汇总是自动开启的。

R2：router eigrp 110 network 172.16.12.0 0.0.0.255 network 172.16.23.0 0.0.0.255 no auto-summaryR3：router eigrp 110 network 172.16.13.0 0.0.0.255 network 172.16.23.0 0.0.0.255 network 172.16.33.0 0.0.0.255 no auto-summary三、基本链路链通之后，去查看下配置路由协议。这个时候不难发现，处于等价负载均衡的模式。R1#show ip route 172.16.0.0/24 is subnetted, 5 subnetsD 172.16.33.0 [90/2172416] via 172.16.13.3, 03:14:40, Serial0/0D 172.16.23.0 [90/2681856] via 172.16.13.3, 03:14:40, Serial0/0 [90/2681856] via 172.16.12.2, 03:14:40, Serial0/1(在这里我可以很好的发现，去往23网段的路径有两条。并且开销都是一样的。)C 172.16.12.0 is directly connected, Serial0/1C 172.16.13.0 is directly connected, Serial0/0C 172.16.11.0 is directly connected, Loopback0

四、为了使得去往23网段的R2路径成为可行继任者，接下来进行配置R1的度量值。

R1(config)#interface s0/0R1(config-if)#delay 1000000(在去往R3的出接口上进行配置度量值。使得R2能够成为可行继任者。（度量值是在接口上进行配置）

五、现在再次去查看路由表的时候，这个时候。你可以发现路由表中只出现一条去往23网段的路由条目。（这个时候你是不是会怀疑，为什么变成一条了。但事实上并没有消失，只是因为不是最有路由，没有放在路由表中。但并不代表不存在，在拓扑表中能够发现。)R1#show ip route 172.16.0.0/24 is subnetted, 5 subnetsD 172.16.33.0 [90/2809856] via 172.16.12.2, 03:28:31, Serial0/1D 172.16.23.0 [90/2681856] via 172.16.12.2, 03:28:31, Serial0/1C 172.16.12.0 is directly connected, Serial0/1C 172.16.13.0 is directly connected, Serial0/0C 172.16.11.0 is directly connected, Loopback0
去查看拓扑表：R1#show ip eigrp topologyIP-EIGRP Topology Table for AS(110)/ID(172.16.11.1)P 172.16.33.0/24, 1 successors, FD is 2809856 via 172.16.12.2 (2809856/2297856), Serial0/1 via 172.16.13.3 (27385856/128256), Serial0/0P 172.16.23.0/24, 1 successors, FD is 2681856 via 172.16.12.2 (2681856/2169856), Serial0/1 via 172.16.13.3 (27769856/2169856), Serial0/0P 172.16.12.0/24, 1 successors, FD is 2169856 via Connected, Serial0/1P 172.16.13.0/24, 1 successors, FD is 27257856 via Connected, Serial0/0P 172.16.11.0/24, 1 successors, FD is 128256 via Connected, Loopback0六、为了实现在不等价负载均衡，接着去路由协议里面去配置variance值。这样就能够实现不等价负载均衡。R1(config)#router eigrp 110R1(config-router)#variance 20
此外，在接口上进行修改延长。R1(config)#interface serial 0R1(config-if)#delay 1000000
七、现在再次去查看路由表，这个时候就能发现在路由表中有两条去往同一目的地的又有条目。但是他们的开销却是不同的。R1#show ip route
172.16.0.0/24 is subnetted, 5 subnetsD 172.16.33.0 [90/27385856] via 172.16.13.3, 03:44:57, Serial0/0 [90/2809856] via 172.16.12.2, 03:44:57, Serial0/1D 172.16.23.0 [90/27769856] via 172.16.13.3, 03:44:57, Serial0/0 [90/2681856] via 172.16.12.2, 03:44:57, Serial0/1C 172.16.12.0 is directly connected, Serial0/1C 172.16.13.0 is directly connected, Serial0/0C 172.16.11.0 is directly connected, Loopback0
到这里实验基本完成！！！！！