User Guide    699
Configuring DHCP Filter DHCPv4 Filter Configuration
Follow these steps to add a legal DHCPv4 server:
1)  Configure the following parameters:
Server IP Address Specify the IP address of the legal DHCPv4 server.
Client MAC 
Address
(Optional) Specify the MAC address of the DHCP Client. You can also keep this 
field empty, which represents for all DHCP clients.
Server Port Select the port that the legal DHCPv4 server is connected.
2)  Click Create.
2.2  Using the CLI
2.2.1  Configuring the Basic DHCPv4 Filter Parameters
Follow these steps to complete the basic settings of DHCPv4 Filter:
Step 1 configure
Enter global configuration mode.
Step 2 ip dhcp filter
Enable DHCPv4 Filter globally.
Step 3 interface {
 
fastEthernet 
port 
|
 
range fastEthernet 
port-list 
| gigabitEthernet
 port
 | range
 
gigabitEthernet
 port-list 
| ten-gigabitEthernet
 port
 | range
 
ten-gigabitEthernet
 port-list 
| 
interface port-channel
 port-channel-id
 | interface range
 
port-channel 
port-channel-id-list 
}
Enter interface configuration mode.
Step 4 ip dhcp filter
Enable DHCPv4 Filter on the port.
Step 5 ip dhcp filter mac-verify
Enable the MAC Verify feature. There are two fields in the DHCP packet that contain the 
MAC address of the host. The MAC Verify feature compares the two fields of a DHCP 
packet and discards the packet if the two fields are different. This prevents the IP address 
resource on the DHCP server from being exhausted by forged MAC addresses.
Step 6 ip dhcp filter limit rate 
value
Enable the limit rate feature and specify the maximum number of DHCP messages that can 
be forwarded on the port per second. The excessive DHCP packets will be discarded. 
value: 
Specify the limit rate value. The following options are provided: 0, 5,10,15,20,25 and 
30 (packets/second). The default value is 0, which indicates disabling limit rate.
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