Configuring Dhcp Snooping To Support Option 82; Prerequisites - H3C S5120-SI Series Configuration Manual

You need to specify the ports connected to the valid DHCP servers as trusted to ensure that DHCP clients can
•
obtain valid IP addresses. The trusted port and the port connected to the DHCP client must be in the same
VLAN.
You can specify Layer 2 Ethernet interfaces and Layer 2 aggregate interfaces as trusted ports. For details about
•
aggregate interfaces, refer to Ethernet Link Aggregation Configuration in the Layer 2 - LAN Switching
Configuration Guide.
If a Layer 2 Ethernet interface is added to an aggregation group, DHCP snooping configured on the interface
•
will not take effect. After the interface quits from the aggregation group, DHCP snooping will be effective.

Configuring DHCP snooping to support Option 82

Prerequisites

Enable the DHCP snooping function before you configure DHCP snooping to support Option 82.

Configuring DHCP snooping to support Option 82

To configure DHCP snooping to support Option 82:
To do...
1. Enter system view
2. Enter interface view
3. Enable DHCP snooping to support
Option 82
4. Configure the handling strategy for
requesting messages containing Option
82
5. Configure non-
user-defined
Option 82
Use the command...
system-view
interface interface-type
interface-number
dhcp-snooping
information enable
dhcp-snooping
information strategy {
drop | keep | replace }
dhcp-snooping
information format {
Configure the
normal | verbose [ node-
padding format for
identifier { mac | sysname
Option 82
| user-defined node-
identifier } ] }
50
Remarks
—
—
Required
Disabled by default.
Optional
replace by default.
Optional
normal by default.