内网能够访问外网，外网不能访问内网！（ACL）

1.搭建的拓扑图

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2.配置命令：

R7(config)#ip access-list extended ref_gjp

R7(config-ext-nacl)#permit ip 192.168.1.0 0.0.0.255 any reflect ref_gjp1

R7(config-ext-nacl)#exit

R7(config)#ip access-list extended ref_gjp2

R7(config-ext-nacl)#evaluate ref_gjp1

R7(config)#int f1/0

R7(config-if)#ip access-group ref_gjp out

R7(config-if)#ip access-group ref_gjp2 in

R7(config-if)#end

3. 配置截图：

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测试:

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R7#show ip access-list

Extended IP access list ref_gjp

10 permit ip 192.168.1.0 0.0.0.255 any reflect ref_gjp1 (41 matches)

Reflexive IP access list ref_gjp1

permit icmp host 192.168.101.128 host 192.168.1.10 (14 matches) (time left 240)

Extended IP access list ref_gjp2

10 evaluate ref_gjp1

<a href="http://5645432.blog.51cto.com/attachment/201208/7/5635432_13443463836VY8.jpg"></a>

(如有误，请多多指教！)

本文转自 gjp0731 51CTO博客，原文链接:http://blog.51cto.com/guojiping/957706