
Operation Manual – DHCP
H3C S5600 Series Ethernet Switches
Chapter 4 DHCP Snooping Configuration
4-14
4.3.2 IP Filtering Configuration Example
I. Network requirements
As shown in
Figure 4-7
, GigabitEthernet 1/0/1 of the S5600 switch is connected to the
DHCP server and GigabitEthernet 1/0/2 is connected to Host A. The IP address and
MAC address of Host A are 1.1.1.1 and 0001-0001-0001 respectively. GigabitEthernet
1/0/3 and GigabitEthernet 1/0/4 are connected to DHCP Client B and Client C.
z
Enable DHCP snooping on the switch, and specify GigabitEthernet 1/0/1 as the
DHCP snooping trusted port.
z
Enable IP filtering on GigabitEthernet 1/0/2, GigabitEthernet 1/0/3, and
GigabitEthernet 1/0/4 to prevent attacks to the server from clients using fake
source IP addresses.
z
Create static binding entries on the switch, so that Host A using a fixed IP address
can access external networks.
II. Network diagram
Switch
DHCP Snooping
Host A
IP:1.1.1.1
MAC:0001-0001-0001
GE1/0/2
Client C
GE1/0/4
GE1/0/1
DHCP Server
Client B
GE1/0/3
Figure 4-7
Network diagram for IP filtering configuration
III. Configuration procedure
# Enable DHCP snooping on the switch.
<Switch> system-view
[Switch] dhcp-snooping
# Specify GigabitEthernet 1/0/1 as the trusted port.
[Switch] interface GigabitEthernet1/0/1
[Switch-GigabitEthernet1/0/1] dhcp-snooping trust
[Switch-GigabitEthernet1/0/1] quit