DHCP的三種配置方法

DHCP配置

dhcp request ：由用戶發向服務器的廣播報文，目的是用來通知其他服務器是否使用服務器分配的ip地址。同時該報文還有續租的作用。
dhcp 租期： 目的是合理有效的使用ip地址。分配給客戶端的ip地址都是有租期的，當到達租期一半的時候，客戶端會自動觸發續租消息（dhcp request報文）。

DHCP協議報文：
DHCPDISCOVER: 由客戶端廣播來查找可用的服務器
DHCP OFFER: 服務器用來響應客戶端的DHCP DISCOVER報文，并指定相應的配置參數。
DHCP REQUEST: 由客戶端發送給服務器來請求配置參數或者請求配置確認或者續借租期。
DHCP ACK: 由服務器到客戶端，含有配置參數包括IP地址。

DHCP高級報文：
DHCP DECLINE： 當客戶端發現地址已經被使用時，用來通知服務器。
DHCP INFORM： 客戶端已經有IP地址時用它來向服務器請求其他的配置參數。
DHCP NAK： 由服務器發送給客戶端來表明客戶端的地址請求不正確或者租期已過期。
DHCP RELEASE： 客戶端要釋放地址時用來通知服務器。

DHCP配置

全局建立地址池

[Huawei]ip pool xiaoguo [Huawei-ip-pool-xiaoguo]gateway-list 192.168.1.1 [Huawei-ip-pool-xiaoguo]network 192.168.1.0 mask 24 [Huawei-ip-pool-xiaoguo]dns-list 8.8.8.8 [Huawei]interface GigabitEthernet 0/0/0 [Huawei-GigabitEthernet0/0/0]dhcp select global

修改租期(可選)

[Huawei]ip pool xiaoguo [Huawei-ip-pool-xiaoguo]lease day 0 hour 20

綁定固定mac對應IP(可選)

[Huawei]ip pool xiaoguo [Huawei-ip-pool-xiaoguo]static-bind ip-address 192.168.1.254 mac-address 5489-98E4-199F

排除地址段(可選)

[Huawei]ip pool xiaoguo [Huawei-ip-pool-xiaoguo]excluded-ip-address 192.168.1.200 192.168.1.250

調試指令：顯示已經分配的ip地址的使用情況

[Huawei]display ip pool name xiaoguo used

重置分配記錄

<Huawei>reset ip pool name xiaoguo used

2.基于接口的dhcp(簡單、便捷)

[Huawei]interface GigabitEthernet 0/0/0 [Huawei-GigabitEthernet0/0/0]ip address 192.168.1.1 24 [Huawei-GigabitEthernet0/0/0]dhcp select interface [Huawei-GigabitEthernet0/0/0]dhcp server dns-list 8.8.8.8

3.dhcp relay(dhcp中繼)

sw1:<Huawei>system-view [Huawei]sysname sw1 [sw1]undo info-center enable [sw1]vlan batch 10 20 800[sw1]dhcp enable [sw1]interface Vlanif 800[sw1-Vlanif800]ip add 192.168.254.1 24[sw1]interface Vlanif 10[sw1-Vlanif10]ip add 192.168.10.1 24[sw1-Vlanif10]dhcp select relay [sw1-Vlanif10]dhcp relay server-ip 192.168.254.2[sw1]interface Vlanif 20[sw1-Vlanif20]ip add 192.168.20.1 24[sw1-Vlanif20]dhcp select relay[sw1-Vlanif20]dhcp relay server-ip 192.168.254.2[sw1]interface GigabitEthernet 0/0/1 [sw1-GigabitEthernet0/0/1]port link-type access [sw1-GigabitEthernet0/0/1]port default vlan 800[sw1-GigabitEthernet0/0/1]int g0/0/2 [sw1-GigabitEthernet0/0/2]port link-type trunk [sw1-GigabitEthernet0/0/2]port trunk allow-pass vlan 10[sw1-GigabitEthernet0/0/2]int g0/0/3 [sw1-GigabitEthernet0/0/3]port link-type trunk [sw1-GigabitEthernet0/0/3]port trunk allow-pass vlan 20sw2:<Huawei>system-view [Huawei]sysname sw2[sw2]vlan 10[sw2]interface e0/0/1[sw2-Ethernet0/0/1]port link-type trunk [sw2-Ethernet0/0/1]port trunk allow-pass vlan 10[sw2-Ethernet0/0/1]int e0/0/2[sw2-Ethernet0/0/2]port default vlan 10sw3:<Huawei>system-view [Huawei]sysname sw3[sw3]vlan 20[sw3]int e0/0/1[sw3-Ethernet0/0/1]port link-type trunk[sw3-Ethernet0/0/1]port trunk allow-pass vlan 20[sw3-Ethernet0/0/1]int e0/0/2[sw3-Ethernet0/0/2]port link-type access[sw3-Ethernet0/0/2]port default vlan 20R1:[Huawei]sysname R1-DHCP[R1-DHCP]int g0/0/0[R1-DHCP-GigabitEthernet0/0/0]dhcp select global [R1-DHCP-GigabitEthernet0/0/0]ip add 192.168.254.2 24[R1-DHCP]ip route-static 0.0.0.0 0 192.168.254.1[R1-DHCP]ip pool vlan10[R1-DHCP-ip-pool-vlan10]network 192.168.10.0 mask 24[R1-DHCP-ip-pool-vlan10]gateway-list 192.168.10.1[R1-DHCP-ip-pool-vlan10]dns-list 8.8.8.8[R1-DHCP]ip pool vlan20[R1-DHCP-ip-pool-vlan20]network 192.168.20.0 mask 24[R1-DHCP-ip-pool-vlan20]gateway-list 192.168.20.1[R1-DHCP-ip-pool-vlan20]dns-list 8.8.8.8