路由政策3_Distribute-list3

拓撲圖：

基本配置：

R1,R2 192.168.12.0/24

R2,R3 192.168.23.0/24

R1:

interface Loopback0

 ip address 1.1.1.1 255.255.255.0

 ip ospf network point-to-point

!

interface Loopback1

 ip address 10.10.10.10 255.255.255.0

 ip ospf network point-to-point //指定OSPF網絡類型避免loopback接口問題

在沒有配置分發清單前各路由器的路由表：

r1#sh ip rou

C    192.168.12.0/24 is directly connected, Serial0/0

     1.0.0.0/24 is subnetted, 1 subnets

C       1.1.1.0 is directly connected, Loopback0

     10.0.0.0/24 is subnetted, 1 subnets

C       10.10.10.0 is directly connected, Loopback1

O    192.168.23.0/24 [110/128] via 192.168.12.2, 00:01:45, Serial0/0

r1#

R2：

r2#sh ip rou

O       1.1.1.0 [110/65] via 192.168.12.1, 00:01:32, Serial0/0

O       10.10.10.0 [110/65] via 192.168.12.1, 00:01:32, Serial0/0

C    192.168.23.0/24 is directly connected, Serial0/1

r2#

R3:

r3#sh ip rou

O    192.168.12.0/24 [110/128] via 192.168.23.1, 00:01:14, Serial0/0

O       1.1.1.0 [110/129] via 192.168.23.1, 00:01:14, Serial0/0

O       10.10.10.0 [110/129] via 192.168.23.1, 00:01:14, Serial0/0

C    192.168.23.0/24 is directly connected, Serial0/0

r3#

可以看到各路由器都學習到了全網的路由。下面配置分發清單：

配置參數：

r2(config)#acc 1 den 10.10.10.0

r2(config)#acc 1 per an

r2(config)#router os 1

r2(config-router)#distrib 1 in s0/0

檢視配置效果：

<b>O       1.1.1.0 [110/65] via 192.168.12.1, 00:00:26, Serial0/0</b>

<b></b>

可以看到R2的路由表中沒有10.10.10.0/24的路由了，但R3的路由表中還是有的，

r3#clear ip route *

O    192.168.12.0/24 [110/128] via 192.168.23.1, 00:00:01, Serial0/0

O       1.1.1.0 [110/129] via 192.168.23.1, 00:00:01, Serial0/0

<b>O       10.10.10.0 [110/129] via 192.168.23.1, 00:00:01, Serial0/0</b>

因為OSPF是鍊路狀态路由協定，是通過LSA來更新路由表的。下面可以在R2檢視10.10.10.0/24的LSA.

<b>r2#show ip ospf database</b>

            OSPF Router with ID (192.168.23.1) (Process ID 1)

                Router Link States (Area 0)

Link ID         ADV Router      Age         Seq#       Checksum Link count

<b>10.10.10.10     10.10.10.10     339         0x80000004 0x00C3DC 4</b>

192.168.23.1    192.168.23.1    346         0x80000004 0x00D194 4

192.168.23.2    192.168.23.2    382         0x80000002 0x000416 2

<b>r2#show ip os database router 10.10.10.10</b>

  LS age: 368

  Options: (No TOS-capability, DC)

  LS Type: Router Links

  Link State ID: 10.10.10.10

  Advertising Router: 10.10.10.10

  LS Seq Number: 80000004

  Checksum: 0xC3DC

  Length: 72

  Number of Links: 4

    Link connected to: a Stub Network

<b>     (Link ID) Network/subnet number: 10.10.10.0</b>

     (Link Data) Network Mask: 255.255.255.0

      Number of TOS metrics: 0

       TOS 0 Metrics: 1

     (Link ID) Network/subnet number: 1.1.1.0

    Link connected to: another Router (point-to-point)

     (Link ID) Neighboring Router ID: 192.168.23.1

     (Link Data) Router Interface address: 192.168.12.1

       TOS 0 Metrics: 64

     (Link ID) Network/subnet number: 192.168.12.0

可以得出分發清單的IN方向在OSPF中隻能到本路由器有作用！！！

      本文轉自810105851 51CTO部落格，原文連結：http://blog.51cto.com/4708948/1131402，如需轉載請自行聯系原作者