实验目的：

1、掌握DHCP基本配置实现地址自动分配。

2、理解DHCP的实现原理。

实验拓扑：

实验步骤：

1、依据图中拓扑，在SW1上架设DHCP服务，为不同VLAN的主机动态提供IP信息，配置如下：

SW1(config)#ip dhcp pool VLAN10 

SW1(dhcp-config)#network 192.168.10.0 255.255.255.0 

SW1(dhcp-config)#default-router 192.168.10.254 

SW1(dhcp-config)#dns-server 8.8.8.8 114.114.114.114 

SW1(dhcp-config)#lease 7 

SW1(dhcp-config)#exit

SW1(config)#ip dhcp pool VLAN20

SW1(dhcp-config)#network 192.168.20.0 255.255.255.0

SW1(dhcp-config)#default-router 192.168.20.254

SW1(dhcp-config)#dns-server 8.8.8.8 114.114.114.114

SW1(dhcp-config)#lease 7

SW1(dhcp-config)#exit

2、在DHCP Client将IP设置为动态学习方式，如下：

PC1(config)#int f0/0

PC1(config-if)#ip address dhcp  

PC1(config-if)#exit

PC2(config)#int f0/0

PC2(config-if)#ip address dhcp

PC2(config-if)#exit

3、检测DHCP分配情况，如下：

①在DHCP Client上，查看地址是否学到

PC1#show ip int brief

Interface     IP-Address    OK?  Method   Status    Protocol

FastEthernet0/0  192.168.10.1 YES  DHCP     up        up 

PC2#show ip int brief

Interface     IP-Address    OK?  Method   Status    Protocol

FastEthernet0/0  192.168.20.1 YES  DHCP    up        up

从上面可以看出，PC的地址已经学到，并且地址学习方式从手工方式变成DHCP方式。

②在DHCP Server上，查看DHCP地址池分配情况

R1#show ip dhcp pool

Pool VLAN10 :

 Utilization mark (high/low)    : 100 / 0

 Subnet size (first/next)       : 0 / 0

 Total addresses                : 254 

 Leased addresses               : 1 

 Pending event                  : none

 1 subnet is currently in the pool :

 Current index   IP address range                    Leased addresses

 192.168.10.2    192.168.10.1 - 192.168.10.254            1


Pool VLAN20 :

 Utilization mark (high/low)    : 100 / 0

 Subnet size (first/next)       : 0 / 0

 Total addresses                : 254

 Leased addresses               : 1

 Pending event                  : none

 1 subnet is currently in the pool :

 Current index   IP address range                    Leased addresses

 192.168.20.2     192.168.20.1 - 192.168.20.254          1

查看DHCP地址分配，以及主机情况，如下：

R1#show ip dhcp binding

Bindings from all pools not associated with VRF:

IP address          Client-ID/              Lease expiration        Type

                    Hardware address/

                    User name

192.168.10.1        0063.6973.636f.2d63.    Mar 08 2002 12:37 AM    Automatic

                    6330.352e.3330.3963.

                    2e30.3030.302d.4661.

                    302f.30

192.168.20.1        0063.6973.636f.2d63.    Mar 08 2002 12:38 AM    Automatic

                    6330.362e.3330.3963.

                    2e30.3030.302d.4661.

                    302f.30

从上面结果可以看到，通过部署DHCP技术，可以使主机更方便接入网络。尤其是移动互联网时代，DHCP技术越发彰显其重要性，各种终端如PC、手机、平板需要更方便的连入网络，所以除了常规的企业网络，在现在的公共WIFI场所如公交、地铁、咖啡馆等，DHCP技术的应用也是非常广泛。此实验完成。