H3C S6850 Series Configuration Guide

10
Configuring many-to-one VLAN mapping in static IP address
assignment environment
About many-to-one VLAN mapping in static IP address assignment environment
In a network that uses static IP addresses, configure many-to-one VLAN mapping with ARP
snooping.
The switch replaces the SVLAN tag of the downlink traffic with the associated CVLAN tag based on
the ARP snooping entry lookup.
Restrictions and guidelines for many-to-one VLAN mapping in static IP address assignment
environment
When you configure many-to-one VLAN mapping in a network that uses static address assignment,
follow these restrictions and guidelines:
• Make sure hosts in different CVLANs do not use the same IP address.
• When an IP address is no longer associated with the MAC address and VLAN in an ARP
snooping entry, wait for this entry to be aged out. You can also use the
reset arp snooping
ip ip-address command to clear the entry.
• Before you modify many-to-one VLAN mapping, use the
reset arp snooping vlan
vlan-id command to clear the ARP snooping entries in each CVLAN.
• To ensure correct traffic forwarding from the service provider network to the customer network,
do not configure many-to-one VLAN mapping together with uRPF. For more information about
uRPF, see Security Configuration Guide.
Many-to-one VLAN mapping in static IP address assignment environment tasks at a glance
To configure many-to-one VLAN mapping in static IP address assignment environment, perform the
following tasks:
1. Enabling ARP snooping
2. Configuring the customer-side port
3. Configuring the network-side port
Enabling ARP snooping
1. Enter system view.
system-view
2. Enter VLAN view.
vlan vlan-id
3. Enable ARP snooping.
arp snooping enable
By default, ARP snooping is disabled.
You must enable ARP snooping for the original VLANs and the translated VLANs.
Configuring the customer-side port
1. Enter system view.
system-view
2. Enter interface view.
{ Enter Layer 2 Ethernet interface view.
interface interface-type interface-number
{ Enter Layer 2 aggregate interface view.
interface bridge-aggregation interface-number

H3C S6850 Series Specifications

General

Brand	H3C
Model	S6850 Series
Category	Switch
Language	English