H3C Technologies H3C S12500 Series Switches - Manual (Page 40)

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Configuring the super VLAN
Overview
Super VLAN, also called VLAN aggregation, was introduced to save IP address space.
A super VLAN is associated with multiple sub-VLANs. You can create a VLAN interface for a super VLAN
and assign an IP address to the VLAN interface. However, you cannot create a VLAN interface for a
sub-VLAN. You cannot assign a physical port to a super VLAN, but you can assign a physical port to a
sub-VLAN. All ports of a sub-VLAN use the VLAN interface IP address of the associated super VLAN.
Packets cannot be forwarded between sub-VLANs at Layer 2.
To enable Layer 3 communication between sub-VLANs, you should configure the VLAN interface IP
address of the associated super VLAN as the gateway IP address. This enables multiple sub-VLANs to
share the same gateway address, which saves IP address resources.
After creating a super VLAN and the VLAN interface, enable local proxy Address Resolution Protocol
(ARP) on the switch. The super VLAN can use local proxy ARP to forward and process ARP requests and
responses and to provide Layer 3 communication between sub-VLANs. For more information about local
proxy ARP, see Layer 3—IP Services Configuration Guide.
Configuration procedure
To configure a super VLAN, complete the following tasks:
1. Configure sub-VLANs.
2. Configure a super VLAN, and associate the super VLAN with the sub-VLANs configured earlier.
3. Configure a VLAN interface for the super VLAN. The VLAN interface enables communication
among hosts and sub-VLANs.
Configuring sub-VLANs
Step Command Remarks
1. Enter system view. system-view N/A
2. Create a sub-VLAN and enter
VLAN view.
vlan vlan-id
If the specified VLAN already
exists, this command enters VLAN
view only.
Configuring a super VLAN
When you configure a super VLAN, follow these guidelines:
• Do not configure a VLAN as a super VLAN and a sub-VLAN at the same time.
• To make Layer 2 multicast take effect on a sub-VLAN, you must enable Layer 2 multicast on the
sub-VLAN and the associated super VLAN at the same time.
• A super VLAN supports Layer 3 multicast. When the multicast source is in a sub-VLAN associated
with the super VLAN, the multicast source can forward multicast streams to the multicast receivers in
the sub-VLAN and forward multicast streams to other Layer 3 interfaces, but the multicast source