aggregate-vlan

Function

The aggregate-vlan command configures a VLAN as a super VLAN.

The undo aggregate-vlan command deletes the configured super VLAN.

By default, no super VLAN is configured.

Format

aggregate-vlan

undo aggregate-vlan

Parameters

None

Views

VLAN view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
vlan	write

Usage Guidelines

Usage Scenario

VLANs are widely used on switching networks because of its flexible control of broadcast domains and convenient deployment. To implement communication between VLANs, you need to create a VLANIF interface for each VLAN and assign an IP address to the VLANIF interface. This wastes IP address resources. To implement communication between VLANs and save IP address resources, configure VLAN aggregation.

In VLAN aggregation, a super VLAN is associated with multiple sub-VLANs. A super VLAN does not support physical interface addition but can have a VLANIF interface and IP address configured. A sub-VLAN supports physical interface addition but cannot have a VLANIF interface configured. All the interfaces in the sub-VLAN use the IP address assigned to the VLANIF interface of the super VLAN. This saves some subnet IDs, subnets' default gateway addresses, directed broadcast addresses as well as eliminates subnet differences by allowing different broadcast domains to use addresses in the same subnet segment. In addition, VLAN aggregation improves addressing flexibility and reduces idle address waste. It allows each sub-VLAN to function as a broadcast domain to implement broadcast isolation and saves IP address resources.

To configure a VLAN as a super VLAN, run the aggregate-vlan command.

Prerequisites

No physical interfaces are added to the VLAN. If the VLAN contains physical interfaces, delete the physical interfaces first.

Follow-up Procedure

Run the access-vlan command in the super VLAN view to add one or more sub-VLANs to the super VLAN.

Precautions

A super VLAN must have a different VLAN ID from sub-VLANs.

A super VLAN is composed of sub-VLANs and does not support physical interface addition.

The IP address of the VLANIF interface of a super VLAN must cover the subnet segments where users in sub-VLANs reside. The sub-VLANs all use the IP address of the VLANIF interface of the super VLAN.

On a specified VLANIF interface that is bound to a BFD session, BFD fails if the aggregate-vlan command is run to configure the VLAN as a super VLAN.

Example

# Configure VLAN 2 as a super VLAN.

<HUAWEI> system-view
[~HUAWEI] vlan 2
[*HUAWEI-vlan2] aggregate-vlan