一、实验拓扑图：

二、实验目的

   1、在实验中应用到高级路由功能来操作路由更新，这些特性包括分发列表，默认路由，被动接口和路由重分布。

2、掌握高级路由特性来控制路由更新。

三、实验要求

1、公司的Guangzhou和Beijing之间的网络使用的RIPV2动态路由协议。

2、在Guangzhou上面连接了一个stub network 172.16.5.1/24，为了减少流量，过滤RIPv2更新流量在整个172.16.5.1/24网络发送。

3、在Beijing有Engineers和Managers部门，Managers网络并不想被Guangzhou所学习到。

4、有一条非常慢的19.2Kpbs的链路连接Beijing和Shanghai，为了减少这条链路的流量，我们要禁止动态路由更新通过这条链路

5、在满足上述条件的情况下，实现全网互通。

四、实验步骤

1、按照拓扑图中IP，配置好路由器接口IP地址。配置如下：

Router(config)#host GuangZhou

GuangZhou(config)#int s1/1

GuangZhou(config-if)#ip add 172.16.224.1 255.255.255.252

GuangZhou(config-if)#no shut

GuangZhou(config)#int loop 0

GuangZhou(config-if)#ip add 172.16.5.1 255.255.255.0

GuangZhou(config-if)#exit

BeiJing(config)#int s1/2

BeiJing(config-if)#ip add 172.16.240.1 255.255.255.252

BeiJing(config-if)#no shut

BeiJing(config-if)#exit

BeiJing(config)#int loop 0

BeiJing(config-if)#ip add 172.16.232.1 255.255.255.0

BeiJing(config-if)#description Engineers

BeiJing(config-if)#exit

BeiJing(config)#int loop 1

BeiJing(config-if)#ip add 172.16.236.1 255.255.255.0

BeiJing(config-if)#description Manager

BeiJing(config-if)#end

Router(config)#host ShangHai

ShangHai(config)#int s1/1

ShangHai(config-if)#ip add 172.16.240.2 255.255.255.252

ShangHai(config-if)#no shut

ShangHai(config)#int loop 0

ShangHai(config-if)#ip add 172.16.248.1 255.255.255.0

ShangHai(config-if)#end

配置完成后使用CDP 协议检查相邻设备的连通性，例如：

BeiJing#sh cdp nei

Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge

S - Switch, H - Host, I - IGMP, r - Repeater

Device ID        Local Intrfce     Holdtme    Capability  Platform  Port ID

ShangHai         Ser 1/2            177          R        7206VXR   Ser 1/1

GuangZhou        Ser 1/0            178          R        7206VXR   Ser 1/1

2、在Guangzhou路由器上配置RIPv2协议通告物理直连的网络，配置如下：

GuangZhou(config)#router rip

GuangZhou(config-router)#vers

GuangZhou(config-router)#version 2

GuangZhou(config-router)#network 172.16.224.0

GuangZhou(config-router)#network 172.16.5.0

因为172.16.5.0是一个stub network，这个网络里没有路由器或者主机需要RIPv2协议的更新。.因此将Loopback0这个接口配置为被动接口，保证RIP协议更新不在这个接口上通告出去，并保证Beijing也能通过RIP协议学到这个网络配置如下：

GuangZhou(config)#router rip

GuangZhou(config-router)#passive-interface loop 0

这样，RIPv2将不会在loopback0接口上发送路由更新。

3、在Beijing上配置RIPv2协议，只通告Beijung路由器上的网络，配置如下：

BeiJing(config)#router rip

BeiJing(config-router)#version 2

BeiJing(config-router)#network 172.16.224.0

BeiJing(config-router)#exit

然后在Guangzhou上使用show ip route查看路由表信息

GuangZhou#sh ip route

Gateway of last resort is not set

172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks

R       172.16.240.0/30 [120/1] via 172.16.224.2, 00:00:12, Serial1/1

R       172.16.236.0/24 [120/1] via 172.16.224.2, 00:00:12, Serial1/1

R       172.16.232.0/24 [120/1] via 172.16.224.2, 00:00:12, Serial1/1

C       172.16.224.0/30 is directly connected, Serial1/1

C       172.16.5.0/24 is directly connected, Loopback0

已经通常自动汇总学习到了172.16.232.0/24、172.16.236.0/24这两个网络了。

4、现在问题是172.16.236.0/24这个网络并不想让 Guangzhou 学习到，如何来过滤这个路由更新呢？这个时候我们要使用分发列表来控制路由更新。配置如下：

BeiJing#conf t

BeiJing(config)#access-list 1 deny 172.16.236.0 0.0.0.255

BeiJing(config)#access-list 1 permit any

BeiJing(config)#router rip

BeiJing(config-router)#distribute-list 1 out s1/0

BeiJing(config-router)#exit

首先定义个ACL，拒绝172.16.236.0/24这个网络，然后使用分发列表在S1/0的出口方向上，也就是说Beijing不会在s1/0这个接口上发送关于172.16.236.0/24这个网络的更新。接下来我们到 Guangzhou上使用show ip route命令，显示如下：

GuangZhou#clear ip route *

GuangZhou#sh ip route

Gateway of last resort is not set

172.16.0.0/16 is variably subnetted, 4 subnets, 2 masks

R       172.16.240.0/30 [120/1] via 172.16.224.2, 00:00:02, Serial1/1

R       172.16.232.0/24 [120/1] via 172.16.224.2, 00:00:02, Serial1/1

C       172.16.224.0/30 is directly connected, Serial1/1

C       172.16.5.0/24 is directly connected, Loopback0

这时我们发现172.16.236.0/24这个网络已经被过滤掉了。

5、由于要Shanghai是一个stub network，由于链路的带宽只有19.2Kbps所以我们使用一条默认路由来路由本地的流量，配置如下：

ShangHai#conf t

ShangHai(config)#ip route 0.0.0.0 0.0.0.0 172.16.240.1 210

接下来我们在 SanJose3上使用debug ip packet命令后，再回到Shanghai 使用ping 192.168.5.1这个IP地址。可以看到是可以PING 通的。 Debug命令的输出信息如下：

GuangZhou#

*Nov 26 22:51:44.419: IP: s=172.16.224.2 (Serial1/1), d=224.0.0.9, len 72, rcvd 2

*Nov 26 22:51:49.839: IP: s=172.16.224.1 (local), d=224.0.0.9 (Serial1/1), len 52, sending broad/multicast

*Nov 26 22:51:57.551: IP: tableid=0, s=172.16.240.2 (Serial1/1), d=172.16.5.1 (Loopback0), routed via RIB

*Nov 26 22:51:57.551: IP: s=172.16.240.2 (Serial1/1), d=172.16.5.1, len 100, rcvd 4

*Nov 26 22:51:57.555: IP: tableid=0, s=172.16.5.1 (local), d=172.16.240.2 (Serial1/1), routed via FIB

*Nov 26 22:51:57.559: IP: s=172.16.5.1 (local), d=172.16.240.2 (Serial1/1), len 100, sending

*Nov 26 22:51:57.607: IP: tableid=0, s=172.16.240.2 (Serial1/1), d=172.16.5.1 (Loopback0), routed via RIB

*Nov 26 22:51:57.607: IP: s=172.16.240.2 (Serial1/1), d=172.16.5.1, len 100, rcvd 4

*Nov 26 22:51:57.611: IP: tableid=0, s=172.16.5.1 (local), d=172.16.240.2 (Serial1/1), routed via FIB

*Nov 26 22:51:57.611: IP: s=172.16.5.1 (local), d=172.16.240.2 (Serial1/1), len 100, sending

*Nov 26 22:51:57.655: IP: tableid=0, s=172.16.240.2 (Serial1/1), d=172.16.5.1 (Loopback0), routed via RIB

然后我们继续在Shanghai上使用扩展的PING命令，如下：

ShangHai#ping

Protocol [ip]:

Target IP address: 172.16.5.1

Repeat count [5]:

Datagram size [100]:

Timeout in seconds [2]:

Extended commands [n]: y

Source address or interface: 172.16.248.1

Type of service [0]:

Set DF bit in IP header? [no]:

Validate reply data? [no]:

Data pattern [0xABCD]:

Loose, Strict, Record, Timestamp, Verbose[none]:

Sweep range of sizes [n]:

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 172.16.5.1, timeout is 2 seconds:

Packet sent with a source address of 172.16.248.1

.....

Success rate is 0 percent (0/5)

在Guangzhou上的 debug ip packet命令输出如下，可以看到无法PING通。

GuangZhou#

*Nov 26 23:03:15.727: IP: s=172.16.224.1 (local), d=224.0.0.9 (Serial1/1), len 52, sending broad/multicastconft

Translating "conft"...domain server (255.255.255.255)

*Nov 26 23:03:18.375: IP: s=172.16.224.1 (local), d=255.255.255.255 (Serial1/1), len 51, sending broad/multicast

*Nov 26 23:03:18.383: IP: s=172.16.5.1 (local), d=255.255.255.255 (Loopback0), len 51, sending broad/multicast

*Nov 26 23:03:18.387: IP: s=172.16.5.1 (Loopback0), d=255.255.255.255, len 51, unroutable

*Nov 26 23:03:21.383: IP: s=172.16.224.1 (local), d=255.255.255.255 (Serial1/1), len 51, sending broad/multicast

*Nov 26 23:03:21.387: IP: s=172.16.5.1 (local), d=255.255.255.255 (Loopback0), len 51, sending broad/multicast

*Nov 26 23:03:21.395: IP: s=172.16.5.1 (Loopback0), d=255.255.255.255, len 51, unroutable

不能通是因为在Shanghai上根本就没有通往172.16.5.1的路由。

6、为了使172.16.5.0/24和172.16.248.0/24能够互访我们需配置一条从shanghai直接的网段去往172.16.5.0网段的静态路由，并将其重分布到RIP协议中，配置如下：

BeiJing#conf t

BeiJing(config)#ip route 172.16.248.0 255.255.255.0 172.16.240.2 210

然后在将这条静态路由重分布到RIP协议中，配置如下：

Singapore(config)#router rip

Singapore(config-router)#redistribute static metric 2

7、最后在Guangzhou上使用 show ip route查看路由表，显示如下：

GuangZhou#sh ip route

Gateway of last resort is not set

172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks

R       172.16.248.0/24 [120/2] via 172.16.224.2, 00:00:10, Serial1/1

R       172.16.240.0/30 [120/1] via 172.16.224.2, 00:00:10, Serial1/1

R       172.16.232.0/24 [120/1] via 172.16.224.2, 00:00:10, Serial1/1

C       172.16.224.0/30 is directly connected, Serial1/1

C       172.16.5.0/24 is directly connected, Loopback0

可以看到Guangzhou学习到了172.16.248.0/24这个网络的路由，使用扩展的PING命令

源地址使用172.16.5.1到目的地址172.16.248.1，检查能否ping 通。

Guangzhou#ping

Protocol [ip]:

Target IP address: 172.16.248.1

Repeat count [5]:

Datagram size [100]:

Timeout in seconds [2]:

Extended commands [n]: y

Source address or interface: 172.16.5.1

Type of service [0]:

Set DF bit in IP header? [no]:

Validate reply data? [no]:

Data pattern [0xABCD]:

Loose, Strict, Record, Timestamp, Verbose[none]:

Sweep range of sizes [n]:

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 172.16.248.1, timeout is 2 seconds:

!!!!!

Success rate is 100 percent (5/5), round-trip min/avg/max = 8/20/48 ms

本文转自 独钩寒江雪 51CTO博客，原文链接：http://blog.51cto.com/bennie/434544，如需转载请自行联系原作者