H3C Technologies H3C S7500E Series Switches - Manual (Page 293)

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Task Description
Enabling DHCP snooping Enables DHCP snooping globally (required).
Enabling ARP detection in SVLANs Enables ARP detection in all SVLANs (required).
Configuring an uplink policy Configures an uplink policy for the customer-side port (required).
Configuring the customer-side port
Configures VLAN and other settings required for many-to-one
VLAN mapping (required).
Configuring the network-side port
Configures VLAN and other settings required for many-to-one
VLAN mapping (required).
Before changing VLAN mappings on a port, clear all DHCP snooping entries with the reset
dhcp-snooping command (see DHCP Snooping Configuration Commands in the Layer 3 - IP
Services Command Reference ), or re-enable the dynamic address binding function of the IP Source
Guard module on the port by using the undo ip check source command and then the ip check
source command (see IP Source Guard Configuration Commands in the Security Command
Reference ).
Configuration prerequisites
Before configuring many-to-one VLAN mapping:
Make sure that all home users use DHCP to get IP addresses. For how to assign IP addresses
through DHCP, see DHCP Server Configuration in the Layer 3 - IP Services Configuration Guide.
Create CVLANs and SVLANs, and plan CVLANs-to-SVLAN mappings.
When configuring many-to-one VLAN mapping, you cannot create VLAN interfaces for the involved
SVLANs and CVLANs on the switch.
Enabling DHCP snooping
Follow these steps to enable DHCP snooping:
To do... Use the command... Remarks
Enter system view system-view —
Enable DHCP snooping dhcp-snooping
Required
Disabled by default.