在路由器上配置NAT(Network Address Translation)

           

实验目的：

通过配置静态源地址转换，使内网的R4可以访问外网的R5

配置动态源地址转换。使内网的R2可以访问外网的R3

设置R1的f0/0为inside端口，s2/0为outside端口。

实验环境：

拓扑图如上，R1的S2/0口与R3,R5通过FRAME-RELAY交换机连接形成外网。R1的F0/0口通过局域网交换机与R2,R4连接形成内网。

配置实例

R1
conf t
ip nat inside source static 1.1.2.4(local) 1.1.3.5(global)                             /*静态源地址转换
ip nat pool pool1 1.1.3.2 1.1.3.3(global ip)  prefix-length 24                /*创建地址池，动态源地址转换
ip nat inside source list 1 pool pool1                                   /*使ACL与地址池对应
access-list 1 permit 1.1.2.0 0.0.0.255
int f 0/0
ip ad 1.1.2.1 255.255.255.0
ip nat inside                                                                             /*配置f0/0为inside端口
no shut
exit
int s2/0
ip ad 1.1.3.1 255.255.255.0
encap frame
no arp f
no frame inver
frame map ip 1.1.3.3 103 b
frame map ip 1.1.3.5 105 b
ip nat outside                                                                             /*配置s2/0为outside端口
no shut

end

R2
conf t
int f 0/0
ip ad 1.1.2.2 255.255.255.0
no shut
end

R3
conf t
int s2/0
ip ad 1.1.3.3 255.255.255.0
encap frame
no arp f
no frame inver
frame map ip 1.1.3.1 301 b
no shut
end

R4
conf t
int f 0/0
ip ad 1.1.2.4 255.255.255.0
no shut
end

R5
conf t
int s2/0
ip ad 1.1.3.5 255.255.255.0
encap frame
no arp f
no frame inver
frame map ip 1.1.3.1 501 b
no shut
end

校验

R1#sh ip nat statistics
Total active translations: 1 (1 static, 0 dynamic; 0 extended)
Outside interfaces:
  Serial2/0
Inside interfaces:
  FastEthernet0/0
Hits: 0  Misses: 0
Expired translations: 0
Dynamic mappings:
-- Inside Source
[Id: 1] access-list 1 pool pool1 refcount 0
 pool pool1: netmask 255.255.255.0
        start 1.1.3.2 end 1.1.3.3
        type generic, total addresses 2, allocated 0 (0%), misses 0

R1#sh ip nat t
Pro Inside global      Inside local       Outside local      Outside global
--- 1.1.3.5                        1.1.2.4                   ---                           ---