H3C Technologies H3C S3100 Series Switches - Manual (Page 863)

1-6
To do… Use the command… Remarks
Configure a many-to-one VLAN
mapping rule and enable
many-to-one VLAN mapping on
the port
vlan-mapping n-to-1 vlan
old-vlan-id remark new-vlan-id
Required
Repeat this step to map multiple
original VLANs to the target VLAN
z One-to-one VLAN mapping is mutually exclusive with many-to-one VLAN mapping. With
many-to-one VLAN mapping enabled on a port, you cannot enable one-to-one VLAN mapping on
any other port.
z You must assign the downlink port to not only the original VLANs, but also the target VLAN.
Configuring DHCP Snooping Option 82 to Carry the Original VLAN Information
Follow these steps to configure DHCP snooping option 82 to carry the original VLAN information:
To do… Use the command… Remarks
Enter system view system-view —
Globally configure DHCP snooping
option 82 to carry the original
VLAN information
dhcp-snooping information
ignore-vlanmapping
Required
By default, this function is disabled,
and option 82 carries the target
VLAN information.
Enter Ethernet port view of the
downlink port interface interface-type
interface-number
—
Configure DHCP snooping option
82 to carry the original VLAN
information on the port
dhcp-snooping information
ignore-vlanmapping
Required
By default, this function is disabled,
and option 82 carries the target
VLAN information.
Globally configuring DHCP snooping option 82 to carry the original VLAN information takes effect on all
ports.
One-to-One VLAN Mapping Configuration Example
Network Requirements
The network of a community is as shown in Figure 1-5 . Each user has three applications: PC, VoD, and
VoIP, which are assigned to VLAN 1, VLAN 2, and VLAN 3 on the home gateway.
Configure one-to-one VLAN mapping on the corridor switch to differentiate the uplink traffic streams of
different users, so that the distribution switch can identify the user of a traffic stream by VLAN.