Maipu Administration Guide

Configure DHCP Snooping Basic Functions Example

Network Requirements

DHCP Server1 is the valid DHCP server; DHCP Server2 is the invalid DHCP server.
After configuring the DHCP Snooping function, PC1 and PC2 both can get address from DHCP Server1.

Network Topology

Networking of configuring DHCP Snooping basic functions

Figure 7-6 Networking of configuring DHCP Snooping basic functions

Configuration Steps

Step 1: Configure the link type of VLAN and port on Device.

#Create VLAN2.

Device#configure terminal
Device(config)#vlan 2
Device(config-vlan2)#exit

#Configure the link type of port tengigabitethernet0/1-tengigabitethernet0/3 as Access, permitting the services of VLAN2 to pass.

Device(config)#interface tengigabitethernet 0/1-0/3
Device(config-if-range)#switchport mode access
Device(config-if-range)#switchport access vlan 2
Device(config-if-range)#exit

Step 2: Configure the address pool of DHCP Server1 as 192.168.1.100-192.168.1.199 and the address pool of DHCP Server2 as 192.168.2.100-192.168.2.199. (Omitted)

Step 3: Configure the DHCP Snooping function on Device.

#Enable the DHCP Snooping function.

Device(config)#dhcp-snooping

#Configure the port tengigabitethernet0/2 as trust port.

Device(config)#interface tengigabitethernet 0/2
Device(config-if-tengigabitethernet0/2)#dhcp-snooping trust
Device(config-if-tengigabitethernet0/2)#exit

Step 4: Check the result.

#After PC1 and PC2 get the address successfully, view the DHCP Snooping entries on Device.

Device#show dhcp-snooping database  
        dhcp-snooping database: 
        database entries count:2 
        database entries delete time :300 
----------------------------------------------------------------------------------------
macAddr         ipAddr         transtion-id   vlan  interface leaseTime(s)  status      
0013.0100.0002	192.168.1.101  1              2     te0/1     107990        active     ------ 
0013.0100.0001  192.168.1.100  0              2     te0/1     107989        active     ------ 
Total valid DHCP Client binding table for this criterion: 2

PC1 and PC2 both can get address from DHCP Server1.