Command Manual - Network Protocol 
Quidway S6500 Series Ethernet Switches  Chapter 5  DHCP Configuration Commands
 
Huawei Technologies Proprietary 
5-3 
The so called unknown machine is a device which IP and MAC addresses are not 
contained in any DHCP security table entry. 
This configuration takes effect only when the DHCP security feature is enabled on the 
VLAN interface. 
Example 
# Inhibit unknown machines from passing through the DHCP security check on a 
VLAN interface. 
<Quidway> system-view 
System View: return to User View with Ctrl+Z. 
[Quidway] interface vlan-interface 1 
[Quidway-Vlan-interface1] address-check enable 
[Quidway-Vlan-interface1] address-check no-matched enable 
5.1.4  debugging dhcp-relay 
Syntax 
debugging dhcp-relay 
undo debugging dhcp-relay 
View 
User view 
Parameter 
None 
Description 
Using debugging dhcp-relay command, you can enable DHCP relay debugging. 
Using  undo debugging dhcp-relay command, you can disable the DHCP relay 
debugging. 
By default, DHCP relay debugging is disabled. 
For the related command, see dhcp-server ip, dhcp-server, display dhcp-server, 
display dhcp-server interface vlan-interface. 
Example 
# Enable DHCP relay debugging. 
<Quidway> debugging dhcp-relay 
*0.7200205-DHCP-8-dhcp_debug: 
From client to DHCP Server: 
Interface: VLAN-Interface 1 
ServerGroupNo: 0