DHCP中继 NAT 让客户端自动获取ip地址 并ping通外网！

首先给给c1和c2 分vlan 在 交换机R5上设置

R5>en
R5#conf t
R5(config)#vlan 10
R5(config-vlan)#vlan 20
R5(config-vlan)#inter fa1/1
R5(config-if)#switchport access vlan 10
R5(config-if)#inter fa1/2
R5(config-if)#switchport access vlan 20
R5(config-if)#inter fa1/0
R5(config-if)#switchport mode trunk
R5(config-if)#switchport trunk encapsulation d
R5(config-if)#switchport trunk encapsulation dot1q
然后设置DHCP地址池

dhcp>en
dhcp#conf t
dhcp(config)#ip dhcp p
dhcp(config)#ip dhcp pool
dhcp(config)#ip dhcp pool v10
dhcp(dhcp-config)#netw
dhcp(dhcp-config)#network 192.168.10.0 255.255.255.0
dhcp(dhcp-config)#de
dhcp(dhcp-config)#default-router 192.168.10.1
dhcp(dhcp-config)#ip dhcp pool v20
dhcp(dhcp-config)#default-router 192.168.20.1
dhcp(dhcp-config)#network 192.168.20.0 255.255.255.0
dhcp(dhcp-config)#inter fa0/0
dhcp(config-if)#ip add
dhcp(config-if)#ip address 192.168.100.100 255.255.255.0
dhcp(config-if)#no shut
dhcp(config-if)#end
dhcp(config)#ip route 0.0.0.0 0.0.0.0 192.168.100.10
dhcp(config)#do ping 192.168.100.10
Sending 5, 100-byte ICMP Echos to 192.168.100.10, timeout is 2 seconds:
.!!!!

然后设置DHCP中继 在R3上配置！

R3>en
R3#conf t
R3(config)#vlan 10
R3(config-vlan)#vlan 20
R3(config-vlan)#inter vlan 10
R3(config-if)#ip address 192.168.10.1 255.255.255.0
R3(config-if)#ip helper-address 192.168.100.100
R3(config-if)#no shut
R3(config-if)#inter vlan 20
R3(config-if)#ip helper-address 192.168.100.100
R3(config-if)#ip address 192.168.20.1 255.255.255.0
R3(config-if)#no shut
R3(config-if)#inter fa1/1
R3(config-if)#switchport mode trunk
R3(config-if)#switchport trunk encapsulation dot1q
R3(config-if)#inter f0/0
R3(config-if)#sw
R3(config-if)#ip add
R3(config-if)#ip address 192.168.100.10 255.255.255.0
ig-if)#no shut
R3(config-if)#inter fa1
R3(config-if)#inter fa1/2
R3(config-if)#no switchport
R3(config-if)#ip address 192.168.200.10 255.255.255.0
R3(config-if)#no shut
R3(config)#ip default-gateway 192.168.100.1
R3(config)#ip route 0.0.0.0 0.0.0.0 192.168.200.1
R3#ping 192.168.200.1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.200.1, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 16/31/52 ms
R3#ping 202.106.1.2

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 202.106.1.2, timeout is 2 seconds:
!!!!!

 

R3要有3条直连路由。 一条默认路由。 R1要有2条直连和两条静态

 

在出口路由上配置！

interface FastEthernet0/0
 ip address 192.168.200.1 255.255.255.0
 ip nat inside

interface FastEthernet0/1
 ip address 202.106.1.1 255.255.255.252
 ip nat outside
 ip virtual-reassembly
 duplex auto
 speed auto

ip route 192.168.10.0 255.255.255.0 192.168.200.10
ip route 192.168.20.0 255.255.255.0 192.168.200.10

ip nat inside source list 1 interface FastEthernet0/1 overload
access-list 1 permit 192.168.0.0 0.0.255.255

 

S    192.168.10.0/24 [1/0] via 192.168.200.10
     202.106.1.0/30 is subnetted, 1 subnets
C       202.106.1.0 is directly connected, FastEthernet0/1
C    192.168.200.0/24 is directly connected, FastEthernet0/0
S    192.168.20.0/24 [1/0] via 192.168.200.10
R1#ping 202.106.1.2 source 192.168.200.1
Sending 5, 100-byte ICMP Echos to 202.106.1.2, timeout is 2 seconds:
Packet sent with a source address of 192.168.200.1
.!!!!

 

 

R4>en
R4#conf t
R4(config)#inter fa0/0
R4(config-if)#ip address 202.106.1.2 255.255.255.252
R4(config-if)#no shut

ok ping通外网了！