基本步骤：
1)
创建虚接口VLAN 10、20，并且配置IP地址
2)
起路由协议保证可以通
3)
将接口划到相应的vlan中
4)
在虚接口vlan 10下打ip helper address
3550的配置：
hostname 3550
!
!
ip subnet-zero
ip routing
ip dhcp relay information option
!
interface FastEthernet0/4
description connect to DHCP server

switchport access vlan 20

switchport mode access
!
interface FastEthernet0/14

description connect to work01

switchport access vlan 10

switchport mode access
!
interface FastEthernet0/20

description connect to work02

switchport access vlan 10

switchport mode access
!

interface Vlan10

description place workgroup

ip address 172.16.10.1 255.255.255.0
ip helper-address 172.17.10.2
！指向服务器的地址
interface Vlan20

description place servers

ip address 172.17.10.1 255.255.255.0
!
router ospf 10

log-adjacency-changes

network 172.16.0.0 0.0.255.255 area 0

network 172.17.0.0 0.0.255.255 area 0
！起路由协议


SERVER的配置
no ip routing
！仿真成一台PC

ip dhcp excluded-address 172.16.10.1 172.16.10.2
ip dhcp pool test01

network 172.16.10.0 255.255.255.0

default-router 172.16.10.1
!
interface Ethernet0/0

ip address 172.17.10.2 255.255.255.0
!
ip default-gateway 172.17.10.1

！指定网关 vlan20的地址

另外两台路由器仿真成PC使用动态获取IP
No ip routing
interface Ethernet0/0

ip address dhcp

以上完成后，查看work01
看看是否有DHCP获取到地址
work01#sho ip int b
Interface
IP-Address
OK? Method Status
Protocol
Ethernet0/0
172.16.10.4
YES DHCP
up
up

work01#sho ip route
Default gateway is 172.16.10.1
Host
Gateway
Last Use
Total Uses
Interface
ICMP redirect cache is empty

经过了实验才得的那么多数句,需要的朋友会感谢你的

是啊！数据可都是经过实验才得到的哦，真是很不错的类，谢谢

楼主够细心的,你的实验详细记录可以跟其他感兴趣的人一起分享研究.