V7平台DHCP相关功能配置

一：组网需求

    客户需要局域网PC ip地址能自动获取，由我司设备统一提供DHCP SERVER功能。根据客户当前组网，考虑PC网关设备作为DHCP RELAY，DHCP SERVER功能统一在MSR3620_1设备上配置，还有防止其他设备配置DHCP SERVER功能，在我司接入设备S5820V2上配置DHCP SNOOPING功能。

二：组网图

三：配置步骤

DHCP SERVER设备配置

<DHCP-SERVER>dis cur

#

 version 7.1.059, Alpha 7159

#

 sysname DHCP-SERVER

#

 dhcp enable

#

dhcp server ip-pool 3082

 gateway-list 192.168.2.1

 network 192.168.2.0 mask 255.255.255.0

 dns-list 192.168.2.1

#

interface GigabitEthernet0/0

 port link-mode route

 combo enable copper

 ip address 172.16.1.1 255.255.255.252

#

ip route-static 192.168.2.0 24 172.16.1.2  到中继设备的回程路由

DHCP RELAY设备配置

<DHCP-RELAY>dis cur

#

 version 7.1.059, Alpha 7159

#

 sysname DHCP-RELAY

#

 dhcp enable

 dhcp relay client-information record //启用DHCP中继的用户地址表项记录功能, 缺省情况下，DHCP中继用户地址表项记录功能处于关闭状态

#

interface GigabitEthernet0/0

 port link-mode route

 combo enable copper

 ip address 192.168.2.1 255.255.255.0

 dhcp select relay

 dhcp relay server-address 172.16.1.1

#

interface GigabitEthernet0/2

 port link-mode route

 combo enable copper

 ip address 172.16.1.2 255.255.255.252

#

DHCP SNOOPING设备配置

<DHCP-SNOOPING>dis cur

#

 version 7.1.059, Alpha 7159

#

 sysname DHCP-SNOOPING

#

 dhcp snooping enable

#

interface GigabitEthernet1/0/1

 port link-mode bridge

 combo enable fiber

 dhcp snooping trust

#

interface GigabitEthernet1/0/2

 port link-mode bridge

 combo enable fiber

 dhcp snooping binding record///启用端口的DHCP Snooping表项记录功能，缺省情况下，在启用DHCP Snooping功能后， 端口的DHCP Snooping表项记录功能处于关闭状态

#

PC获取地址是192.168.2.3

[PC]dis ip int b（使用交换机模拟PC）

*down: administratively down

(s): spoofing  (l): loopback

Interface                Physical Protocol IP Address      Description

GE1/0/1                  up       up       192.168.2.3     --

 [PC]dis ip routing-table

Destinations : 13       Routes : 13

Destination/Mask   Proto   Pre Cost        NextHop         Interface

0.0.0.0/0          Static  70  0           192.168.2.1     GE1/0/1

0.0.0.0/32         Direct  0   0           127.0.0.1       InLoop0

<DHCP-SERVER>dis dhcp server ip-in-use

IP address       Client identifier/    Lease expiration      Type

                 Hardware address

192.168.2.3      0033-6161-642e-3632-  Nov 16 19:02:51 2014  Auto(C)

<DHCP-RELAY>dis dhcp relay client-information

Total number of client-information items: 1

Total number of dynamic items: 1

Total number of temporary items: 0

IP address       MAC address      Type        Interface            VPN name

192.168.2.3      3aad-629a-0806   Dynamic     GE0/0                N/A

<DHCP-SNOOPING>dis dhcp snooping binding

 1 DHCP snooping entries found.

 IP address      MAC address    Lease        VLAN  SVLAN Interface

 =============== ============== ============ ===== ===== =================

 192.168.2.3     3aad-629a-0806 85618        1     N/A   GE1/0/2

四：配置关键点

第一：server设备需要有到用户网段的回程路由

第二：relay设备需要开启DHCP功能

第三：snooping设备上行端口必须配置为信任端口