3-9 
 
z  If you configure a remote ID sub-option in both system view and on a port, the remote ID sub-option 
configured on the port applies when the port receives a packet, and the global remote ID applies to 
other interfaces that have no remote ID sub-option configured. 
z  If you have configured a remote ID with the vlan vlan-id argument specified, and the other one 
without the argument in Ethernet port view, the former remote ID applies to the DHCP messages 
from the specified VLAN, while the latter one applies to DHCP messages from other VLANs. 
z  In a port aggregation group, you can use this command to configure the primary and member ports 
respectively. When Option 82 is added, however, the remote ID is subject to the one configured on 
the primary port. 
z  The remote ID configured on a port will not be synchronized in the case of port aggregation. 
 
Configure the padding format for Option 82 
Follow these steps to configure the padding format for Option 82: 
Operation  Command  Description 
Enter system view 
system-view 
— 
Configure the padding format 
dhcp-snooping information 
packet-format { extended | 
standard } 
Optional 
By default, the padding format 
is in extended format. 
 
Configuring IP Filtering 
Follow these steps to Configure IP filtering: 
Operation  Command  Description 
Enter system view 
system-view 
— 
Enter Ethernet port view 
interface interface-type 
interface-number 
— 
Enable IP filtering 
ip check source ip-address 
[ mac-address ] 
Required 
By default, this function is 
disabled. 
Create an IP static binding 
entry 
ip source static binding 
ip-address ip-address 
[ mac-address mac-address ] 
Optional 
By default, no static binding 
entry is created.