DHCP中继是现网中常用的地址分配方法，下面介绍常见厂商的配置方法。
HUAWEI设备配置
DHCP SERVER
sysname DHCP SERVER
dhcp enable
//开启DHCP服务
ip pool 1
gateway-list 192.168.1.1
network 192.168.1.0 mask 255.255.255.0
lease day 0 hour 1 minute 0
dns-list 8.8.8.8
ip pool 2
gateway-list 192.168.2.1
network 192.168.2.0 mask 255.255.255.0
lease day 0 hour 1 minute 0
dns-list 8.8.8.8
//配置两个地址池
interface GigabitEthernet0/0/0
ip address 12.0.0.1 255.255.255.252
dhcp select global
//接口选择全局地址池
ip route-static 0.0.0.0 0.0.0.0 12.0.0.2
//配置回程默认路由
AR1配置
sysname AR1
dhcp enable
//开启DHCP服务
interface GigabitEthernet0/0/0
ip address 12.0.0.2 255.255.255.252
interface GigabitEthernet0/0/1
ip address 192.168.1.1 255.255.255.0
dhcp select relay
dhcp relay server-ip 12.0.0.1
interface GigabitEthernet0/0/2
ip address 192.168.2.1 255.255.255.0
dhcp select relay
dhcp relay server-ip 12.0.0.1
//接口选择DHCP relay 模式和服务器IP
配置完成后 PC正常获取到IP地址
思科设备的配置方法
DHCP SERVER 配置
hostname dhcpserver
service dhcp
ip dhcp pool 1
network 192.168.1.0 255.255.255.0
dns-server 8.8.8.8
default-router 192.168.1.1
lease 0 8
interface Ethernet0/0
ip address 12.0.0.1 255.255.255.252
ip route 0.0.0.0 0.0.0.0 Ethernet0/0 12.0.0.2
中继配置
hostname R1
interface Ethernet0/0
ip address 12.0.0.2 255.255.255.252
interface Ethernet0/1
ip address 192.168.1.1 255.255.255.0
ip helper-address 12.0.0.1
//配置DHCP服务器地址
锐捷设备配置
DHCPSERVER配置
hostname DHCPSERVER
service dhcp
ip dhcp pool 1
lease 0 8 0
network 192.168.1.0 255.255.255.0
dns-server 8.8.8.8
default-router 192.168.1.1
interface GigabitEthernet 0/0
no switchport
ip address 12.0.0.1 255.255.255.252
ip route 0.0.0.0 0.0.0.0 GigabitEthernet 0/0 12.0.0.2
中继路由设置
hostname AR1
service dhcp
ip helper-address 12.0.0.1
interface GigabitEthernet 0/0
no switchport
ip address 12.0.0.2 255.255.255.252
interface GigabitEthernet 0/1
no switchport
ip address 192.168.1.1 255.255.255.0
PC（用路由器模拟）上测试正常
