DHCP中继

应用场景：
通常在DHCP分配网段过多的情况下，网关路由器上配置DHCP服务，压力过大，一般我们用第二路由器，或则第二台DHCP服务器来分担业务
实验
拓扑图## 实验步骤
LSW1命令配置如下

sys.                                    #进入系统视图
[Huawei]sys SW1                                 #命名为SW1
[SW1]vlan batch 10 20                           #创建vlan 10  20
[SW1]interface e0/0/1                           #进入接口e0/0/1
[SW1-Ethernet0/0/1]port link-type access        #创建access
[SW1-Ethernet0/0/1]port default vlan 10         #放进vlan 10
[SW1-Ethernet0/0/1]int e0/0/2                   #进入接口e0/0/2
[SW1-Ethernet0/0/2]port link-type access        #创建access
[SW1-Ethernet0/0/2]port default vlan 20         #放进vlan 20
[SW1-Ethernet0/0/2]int e0/0/3                   #进入接口e0/0/3
[SW1-Ethernet0/0/3]port link-type access        #创建access
[SW1-Ethernet0/0/3]port default vlan 10         #放进vlan 10
[SW1-Ethernet0/0/3]int e0/0/4	                #进入接口e0/0/4
[SW1-Ethernet0/0/4]port link-type access        #创建access
[SW1-Ethernet0/0/4]port default vlan 2          #放进vlan 20
[SW1-Ethernet0/0/4]int g0/0/1                   #进入接口g0/0/1
[SW1-GigabitEthernet0/0/1]port link-type trunk  #创建trunk
[SW1-GigabitEthernet0/0/1]port trunk allow-pass vlan 10 20  # 放通vlan 10 20
[SW1-GigabitEthernet0/0/1]un sh                 #开启接口
[SW1-GigabitEthernet0/0/1]
  

AR2配置命令如下

sys                                          #进入系统视图
[Huawei]sys R1                                       #命名为R1
[R1]dhcp enable                                      #开启dhcp
[R1]int g0/0/0.10                                    #进入接口g0/0/0.10
[R1-GigabitEthernet0/0/0.10]dot1q termination vid 10 #归于vlan 10
[R1-GigabitEthernet0/0/0.10]ip add 192.168.10.1 24   #设置IP地址
[R1-GigabitEthernet0/0/0.10]arp broadcast enable     #开启ARP广播
[R1-GigabitEthernet0/0/0.10]un sh                    #接口开启
[R1-GigabitEthernet0/0/0.10]int g0/0/0.20            #进入接口g0/0/0.20
[R1-GigabitEthernet0/0/0.20]dot1q termination vid 20 #归于vlan 20
[R1-GigabitEthernet0/0/0.20]ip add 192.168.20.1 24   #设置IP地址
[R1-GigabitEthernet0/0/0.20]arp broadcast enable     #开启ARP广播
[R1-GigabitEthernet0/0/0.20]un sh                    #接口开启
[R1-GigabitEthernet0/0/0.20]int g0/0/1               #进入接口g0/0/1
[R1-GigabitEthernet0/0/1]ip add 12.0.0.1 24          #设置IP地址
[R1-GigabitEthernet0/0/1]un sh                       #接口开启
[R1-GigabitEthernet0/0/1]int g0/0/2                  #进入接口g0/0/2
[R1-GigabitEthernet0/0/2]ip add 14.0.0.1 24          #设置IP地址
[R1-GigabitEthernet0/0/2]un sh                       #接口开启
[R1-GigabitEthernet0/0/2]quit                        #退出
[R1]int g0/0/0.10                                    #进入接口g0/0/0.10
[R1-GigabitEthernet0/0/0.10]dhcp select relay        #基于DHCP中继
[R1-GigabitEthernet0/0/0.10]dhcp relay server-ip 14.0.0.2 #去14.0.0.2请求
[R1-GigabitEthernet0/0/0.10]un sh                    #接口开启
[R1-GigabitEthernet0/0/0.10]int g0/0/0.20            #进入接口g0/0/0.20
[R1-GigabitEthernet0/0/0.20]dhcp select relay         #基于DHCP中继
[R1-GigabitEthernet0/0/0.20]dhcp relay server-ip 14.0.0.2   #去14.0.0.2请求
[R1-GigabitEthernet0/0/0.20]un sh                     #接口开启
[R1-GigabitEthernet0/0/0.20]q                         #退出
[R1]ip route-static 15.0.0.0 24 12.0.0.2              #静态路由设置
[R1]

AR3命令配置如下

sys                                           #进入系统视图
[Huawei]sys R2                                        #命名为R2
[R2]dhcp enable                                       #开启dhcp
[R2]int g0/0/1                                        #进入接口g0/0/1 
[R2-GigabitEthernet0/0/1]ip add 15.0.0.1 24           #设置IP地址
[R2-GigabitEthernet0/0/1]dhcp select relay            #基于DHCP中继
[R2-GigabitEthernet0/0/1]dhcp relay server-ip 14.0.0.2  #去14.0.0.2请求
[R2-GigabitEthernet0/0/1]un sh                         #接口开启
[R2-GigabitEthernet0/0/1]int g0/0/0                    #进入接口g0/0/0 
[R2-GigabitEthernet0/0/0]ip add 12.0.0.2 24            #设置IP地址
[R2-GigabitEthernet0/0/0]un sh                         #接口开启
[R2-GigabitEthernet0/0/0]q                             #退出
[R2]ip route-static 0.0.0.0 0.0.0.0 12.0.0.1           #默认路由设置
[R2]

AR1命令配置如下

sys                                      #进入系统视图
[Huawei]sys R3                                   #命名为R3
[R3]dhcp enable                                  #开启dhcp
[R3]int g0/0/0                                   #进入接口g0/0/0
[R3-GigabitEthernet0/0/0]ip add 14.0.0.2 24      #设置IP地址
[R3-GigabitEthernet0/0/0]un sh                   #接口开启
[R3-GigabitEthernet0/0/0]q                       #退出
[R3]ip pool dhcp15                               #创建IP dhcp15 池
[R3-ip-pool-dhcp15]network 15.0.0.0 mask 24      #包含15网段的IP
[R3-ip-pool-dhcp15]gateway-list 15.0.0.1         #设置网关
[R3-ip-pool-dhcp15]dns-list 8.8.8.8 2.2.2.2      #域解析
[R3-ip-pool-dhcp15]q                             #退出
[R3]ip pool dhcpvlan10                           #创建IP dhcpvlan10 池
[R3-ip-pool-dhcpvlan10]network 192.168.10.0 mask 24 #包含192.168.10.0网段的IP
[R3-ip-pool-dhcpvlan10]gateway-list 192.168.10.1  #设置网关
[R3-ip-pool-dhcpvlan10]dns-list 8.8.8.8 2.2.2.2  #域解析
[R3-ip-pool-dhcpvlan10]q                         #退出
[R3]ip pool dhcpvlan20                           #创建IP dhcpvlan20 池
[R3-ip-pool-dhcpvlan20]network 192.168.20.0 mask 24 #包含192.168.20.0网段的IP
[R3-ip-pool-dhcpvlan20]gateway-list 192.168.20.1  #设置网关
[R3-ip-pool-dhcpvlan20]dns-list 8.8.8.8 2.2.2.2  #域解析
[R3-ip-pool-dhcpvlan20]q                         #退出
[R3]int g0/0/0                                   #进入接口g0/0/0
[R3-GigabitEthernet0/0/0]dhcp select global      #去全局，请求DHCP服务
[R3-GigabitEthernet0/0/0]q                       #退出
[R3]ip route-static 0.0.0.0 0.0.0.0 14.0.0.1     #默认路由设置

####注：这是虚拟实验，仅供参考##