Operation Manual - DHCP 
Quidway S5600 Series Ethernet Switches-Release 1510  Chapter 2  
DHCP Server Configuration
 
Huawei Technologies Proprietary 
2-16 
Operation  Command  Description 
to DHCP clients 
Configure 
multiple 
interfaces in 
system view
dhcp select  interface 
{  interface  interface-type 
interface-number [ to 
interface-type 
interface-number ] | all } 
to DHCP clients 
 
  Note: 
To prevent malicious attacks to unused sockets and enhance switch security, S5600 
series Ethernet switches provide the following functions: 
z  When DHCP is enabled, sockets UDP 67 and UDP 68 used by DHCP are enabled. 
z  When DHCP is disabled, sockets UDP 67 and UDP 68 are disabled at the same 
time. 
The preceding functions are implemented as follows: 
z  After you configure a DHCP interface address pool by using the dhcp select 
interface command, sockets UDP 67 and UDP 68 will be enabled.   
z  After you delete the DHCP interface address pool by using the undo dhcp select 
interface command and disable all the DHCP functions, sockets UDP 67 and UDP 
68 will be disabled. 
 
2.3.4  Configuring to Assign IP Addresses of DHCP Address Pools to DHCP 
Clients 
You can assign IP addresses by static binding or assign IP addresses dynamically to 
DHCP clients as needed.   
I. Configuring to assign IP addresses by static binding 
Some DHCP clients, such as WWW servers, need fixed IP addresses. This is 
achieved by binding IP addresses to the MAC addresses of these DHCP clients. When 
such a DHCP client applies for an IP address, the DHCP server finds the IP address 
corresponding to the MAC address of the DHCP client, and then assigns the IP 
address to the DHCP client. 
When some DHCP clients send DHCP-DISCOVER packets to the DHCP server to 
apply for IP addresses, they construct client IDs and add them in the 
DHCP-DISCOVER packets. The DHCP server finds the corresponding IP addresses 
based on the client IDs and assigns them to the DHCP clients.