DHCP: 動態主機配置協議? -- 同一分發管理ip地址

基于UDP 67/68端口工作??

網絡中存在DHCP的服務器為需要自動生成ip地址的設備分配ip地址；--C/S模型

成為DHCP服務器的條件：

1. 該設備存在接口或網卡連接到所要分發ip地址的廣播域內
2. 該接口或網卡必須已經配置合法ip地址，且可以正常通訊；

第一步：[Huawei]dhcp enable ??先開啟設備的dhcp服務一臺設備上可以創建多個池塘，但一個池塘只能服務一個廣播域第二步：[Huawei]ip pool wangcai? 創建名為wangcai的dhcp池塘第三步：[Huawei-ip-pool-wangcai]network 192.168.1.0 mask 24 綁定接口第四步：[Huawei-ip-pool-wangcai]gateway-list 192.168.1.1? 該網段網關地址第五步：[Huawei-ip-pool-wangcai]dns-list 192.168.2.11 114.114.114.114 DNS服務器地址第六步[Huawei]interface Eth0/0/0[Huawei-Ethernet0/0/0]dhcp select global ?切記：最后還需要在路由器進行地址分配的接口上再單獨開啟dhcp服務

客戶端基于UDP，源端口68，目標端口67進行廣播請求 -- 源ip-0.0.0.0（無效地址，代表本地無地址）目255.255.255.255

服務器在收到客戶端的請求后，回復提議-- 源端口67，目標68；源ip-本地地址，目標ip（255.255.255.255）華為設備的目標ip為計劃分配給客戶端的ip --- 主要還是靠目標的MAC地址來將提議發送給客戶

客戶端在收到提議后，若確定使用該ip，將應答服務端；服務端最終ack確認后，該ip地址才可以被真正的使用；

注：過程中服務端與客戶端均會使用ARP來進行地址沖突檢測，確認該地址唯一時，才進行分配和使用；

dhcp抓包過程;?

[Huawei-ip-pool-a]excluded-ip-address 192.168.1.10 192.168.1.20? 排除地址 -- 該池塘不能分配的ip地址

[Huawei-ip-pool-a]lease day? 0 hour 0 minute 30 修改租期，默認24小時

實驗部分：

	
[Huawei-ip-pool-a]display current-configuration 
#
sysname Huawei
#
dhcp enable
#
ip pool bgateway-list 192.168.2.1network 192.168.2.0 mask 255.255.255.0dns-list 192.168.1.2
#
ip pool agateway-list 192.168.1.1network 192.168.1.0 mask 255.255.255.0dns-list 192.168.1.2
#
aaaauthentication-scheme defaultauthorization-scheme defaultaccounting-scheme defaultdomain defaultdomain default_adminlocal-user admin password cipher OOCM4m($F4ajUn1vMEIBNUw#local-user admin service-type http
#
firewall zone Localpriority 16
#
interface Ethernet0/0/0ip address 192.168.1.1 255.255.255.0dhcp select global
#
interface Ethernet0/0/1ip address 192.168.2.1 255.255.255.0dhcp select global[Huawei-ip-pool-a]dis ip interface brief 
*down: administratively down
!down: FIB overload down
^down: standby
(l): loopback
(s): spoofing
(d): Dampening Suppressed
The number of interface that is UP in Physical is 3
The number of interface that is DOWN in Physical is 8
The number of interface that is UP in Protocol is 3
The number of interface that is DOWN in Protocol is 8Interface                         IP Address/Mask      Physical   Protocol  
Ethernet0/0/0                     192.168.1.1/24       up         up        
Ethernet0/0/1                     192.168.2.1/24       up         up        
GigabitEthernet0/0/0              unassigned           down       down      
GigabitEthernet0/0/1              unassigned           down       down      
GigabitEthernet0/0/2              unassigned           down       down      
GigabitEthernet0/0/3              unassigned           down       down      
NULL0                             unassigned           up         up(s)     
Serial0/0/0                       unassigned           down       down      
Serial0/0/1                       unassigned           down       down      
Serial0/0/2                       unassigned           down       down      
Serial0/0/3                       unassigned           down       down      
[Huawei-ip-pool-a]

PC>ipconfigLink local IPv6 address...........: fe80::5689:98ff:fe4a:742d
IPv6 address......................: :: / 128
IPv6 gateway......................: ::
IPv4 address......................: 192.168.1.254
Subnet mask.......................: 255.255.255.0
Gateway...........................: 192.168.1.1
Physical address..................: 54-89-98-4A-74-2D
DNS server........................: 192.168.1.2

Link local IPv6 address...........: fe80::5689:98ff:fe97:2d3f
IPv6 address......................: :: / 128
IPv6 gateway......................: ::
IPv4 address......................: 192.168.2.254
Subnet mask.......................: 255.255.255.0
Gateway...........................: 192.168.2.1
Physical address..................: 54-89-98-97-2D-3F
DNS server........................: 192.168.1.2