Cisco 3550 Configuration DHCP Relay Agent

Lab Environment:

1. Configure two VLAN 10 and VLAN 20

VLAN IP address settings: 192.168.10.1 255.255.255.0 (192.168.10.1 is a VLAN 10 gateway address)

VLAN IP Address setting: 192.168.20.1 255.255.255.0 (192.168.20.1 is a VLAN 20 gateway address)

2. (Windows Server R2 operating system) set up a DHCP server to create two scopes VLAN 10 and VLAN 20,

Get the IP address dynamically using VLAN 10 and VLAN 20. The DHCP server NIC accesses the switch FA0/1 port.

DHCP server network card settings:

ip:192.168.10.200

Subnet Mask: 255.255.255.0

Gateway: 192.168.10.1

dns1:192.168.10.5 (no DNS server set up, just test use)

dns2:192.168.10.28 (no DNS server set up, just test use)

Annotations: The Cisco 3550 does not support NAT forwarding, and if the upper layer configures a route to do NAT forwarding, the Internet function can be configured.

Implementation features:

1, VLAN 10 and VLAN 20 can ping each other

2, computer access to different VLANs can automatically obtain an IP address

1 , create VLAN ten and VLAN

#特权模式下进入VLAN Sub-mode

switch#VLAN Database

#创建VLAN 10 named Vlan10

Switch (VLAN) #VLAN ten name Vlan10

#创建VLAN 20 named Vlan20

Switch (VLAN) #VLAN # name Vlan20

2 , configure VLAN ten and VLAN the IP Address and Gateway

#全局模式下进入VLAN 10

Switch (config) #interface VLAN

#配置VLAN 10 IP Address and gateway

Switch (config-if) #IP address 192.168.10.1 255.255.255.0

#退出VLAN 10

Switch (config-if) #Exit

#全局模式下进入VLAN 20

Switch (config) #interface VLAN

#配置VLAN 20 IP Address and gateway

Switch (config-if) #IP address 192.168.20.1 255.255.255.0

#退出VLAN 20

Switch (config-if) #Exit

3 , assigning ports to VLANs and VLAN

#全局模式下进入端口fa0/1 and FA0/2

Switch (config) #interface range FastEthernet 0/1-2

#端口fa0/1 and FA0/2 set working mode for access

Switch (config-if-range) #switchport mode access

#端口fa0/1 and FA0/2 assigned to VLAN 10

Switch (config-if-range) #switchport access VLAN

#激活端口

Switch (config-if-range) #no shutdown

#退出

Switch (config-if-range) #Exit

#全局模式下进入端口fa0/5 and FA0/6

Switch (config) #interface range FastEthernet 0/5-6

#端口fa0/5 and FA0/6 set working mode for access

Switch (config-if-range) #switchport mode access

#端口fa0/5 and FA0/6 assigned to VLAN 20

Switch (config-if-range) #switchport access VLAN

#激活端口

Switch (config-if-range) #no shutdown

#退出

Switch (config-if-range) #Exit

#全局模式下开启路由 so that VLANs can access each other

Switch (config) #IP Routing

4 , the VLAN to which the computer belongs Configuring the Relay Agent

#全局模式下进入VLAN 10

Switch (config) #interface VLAN

#配置VLAN 10 Relay Agent, 192.168.10.200 is the DHCP server address

Switch (config-if) #IP helper-address 192.168.10.200

#退出VLAN 10

Switch (config-if) #Exit

#全局模式下进入VLAN 20

Switch (config) #interface VLAN

#配置VLAN 20 Relay Agent, 192.168.10.200 is the DHCP server address

Switch (config-if) #IP helper-address 192.168.10.200

#退出VLAN 20

Switch (config-if) #Exit

5 , save, and view operations

#特权模式下执行保存配置

switch#Write

#查看vlan分配端口信息

switch#Show VLAN

#查看当前配置信息

switch#Show Running-config

#查看路由选择表当前状态

switch#show ip route

Cisco 3550 Configuration DHCP Relay Agent