Configuring many-to-one vlan mapping, Configuration prerequisites, Enabling dhcp snooping – H3C Technologies H3C S10500 Series Switches User Manual

Page 211: Enabling arp detection in svlans

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To do...

Use the command...

Remarks

Assign the port to
SVLANs

port trunk permit vlan { vlan-id-list
| all }

Required
By default, a trunk port is in only VLAN 1.

Configuring many-to-one VLAN mapping

Perform many-to-one VLAN mapping on campus switches (see

Figure 63

) to transmit the same type of

traffic from different users in one VLAN.
Perform these tasks to configure many-to-one VLAN mapping:

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).

CAUTION:

Before changing VLAN mappings on a port, clear all DHCP snooping entries by using the reset
dhcp-snooping command (see

Layer 3—IP Services Command Reference).

Configuration prerequisites

Before configuring many-to-one VLAN mapping:

Make sure that all home users obtain IP addresses through DHCP. For how to assign IP addresses
through DHCP, see Layer 3—IP Services Configuration Guide.

Create CVLANs and SVLANs, and plan CVLANs-to-SVLAN mappings.

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.

Enabling ARP detection in SVLANs

The ARP detection function enables a switch to modify the VLAN attributes of ARP packets, which is

impossible under the normal ARP packet processing procedure. For more information about ARP

detection, see Security Configuration Guide.
Follow these steps to enable ARP detection in all SVLANs:

To do...

Use the command...

Remarks

Enter system view

system-view

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