1-4
z
As the default VLAN, VLAN 1 cannot be created or removed.
z
You cannot manually create or remove VLANs reserved for special purposes.
z
Dynamic VLANs cannot be removed with the undo vlan command.
z
A VLAN with a QoS policy applied cannot be removed.
Configuring Basic Settings of a VLAN Interface
For hosts of different VLANs to communicate, you must use a router or Layer 3 switch to perform layer
3 forwarding. To achieve this, VLAN interfaces are used.
VLAN interfaces are virtual interfaces used for Layer 3 communication between different VLANs. They
do not exist as physical entities on devices. For each VLAN, you can create one VLAN interface. You
can assign the VLAN interface an IP address and specify it as the gateway of the VLAN to forward traffic
destined for an IP network segment different from that of the VLAN.
Follow these steps to configure basic settings of a VLAN interface:
To do…
Use the command…
Remarks
Enter system view
system-view
—
Create a VLAN interface and
enter VLAN interface view
interface vlan-interface
vlan-interface-id
Required
If the VLAN interface already exists,
you enter its view directly.
Assign an IP address to the
VLAN interface
ip
address
ip-address
{
mask
|
mask-length
}
Optional
No IP address is assigned to any
VLAN interface by default.
Configure the description of
the VLAN interface
description text
Optional
VLAN interface name is used by
default, for example,
Vlan-interface1 Interface.
Bring up the VLAN interface
undo shutdown
Optional
By default, a VLAN interface is in the
up state. In this case, the VLAN
interface is up so long as one port in
the VLAN is up and goes down if all
ports in the VLAN go down.
An administratively shut down VLAN
interface however will be in the down
state until you bring it up, regardless
of how the state of the ports in the
VLAN changes.
Before creating a VLAN interface for a VLAN, create the VLAN first.
