26
Configuring super VLANs
About super VLANs
Hosts in a VLAN typically use IP addresses in the same subnet. For Layer 3 interoperability with
other VLANs, you can create a VLAN interface for the VLAN and assign an IP address to it. This
requires a large number of IP addresses.
The super VLAN feature was introduced to save IP addresses. A super VLAN is associated with
multiple sub-VLANs. These sub-VLANs use the VLAN interface of the super VLAN (also known as a
super VLAN interface) as the gateway for Layer 3 communication.
You can create a VLAN interface for a super VLAN and assign an IP address to it. However, you
cannot create a VLAN interface for a sub-VLAN. You can assign a physical port to a sub-VLAN, but
you cannot assign a physical port to a super VLAN. Sub-VLANs are isolated at Layer 2.
To enable Layer 3 communication between sub-VLANs, perform the following tasks:
1. Create a super VLAN and the VLAN interface for the super VLAN.
2. Enable local proxy ARP or ND on the super VLAN interface as follows:
{ In an IPv4 network, enable local proxy ARP on the super VLAN interface. The super VLAN
can then process ARP requests and replies sent from the sub-VLANs.
{ In an IPv6 network, enable local proxy ND on the super VLAN interface. The super VLAN
can then process the NS and NA messages sent from the sub-VLANs.
Restrictions and guidelines: Super VLAN
configuration
• The VLAN of a MAC address-to-VLAN entry cannot be configured as a super VLAN.
• A VLAN cannot be configured as both a super VLAN and a guest VLAN, Auth-Fail VLAN, or
critical VLAN. For more information about guest VLANs, Auth-Fail VLANs, and critical VLANs,
see Security Configuration Guide.
• A VLAN cannot be configured as both a super VLAN and a sub-VLAN.
• Layer 2 multicast configuration for super VLANs does not take effect because they do not have
physical ports.
Super VLAN tasks at a glance
To configure a super VLAN, perform the following tasks:
1. Creating a sub-VLAN
2. Configuring a super VLAN
3. Configuring a super VLAN interface
Creating a sub-VLAN
1. Enter system view.
system-view
2. Create a sub-VLAN.