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Chapter 6: VLAN Configuration
Up to 4094 Virtual LANs (VLANs) are supported on the IC35516. The switch is shipped with a default VLAN with
VLAN ID (VID) 1. All switchports (eth1–eth16) are included in the default VID 1.
The
default VID 1 cannot be
deleted
.
6.1 Creating or Modifying a VLAN
Enter the following commands beginning in configuration mode:
Command Purpose
vlan
vid
Enter a VLAN ID (2–4094), which will access config-vlan
mode. Enter a new VLAN ID to create a VLAN, or enter an
existing VLAN ID to modify a VLAN.
name
vlan-name
Enter a name for the VLAN (optional).
end
Return to Enable mode.
no vlan
vid
Enter a VLAN ID (2-4094) to be removed.
Switchports are Layer 2-only interfaces associated with a physical port. A switchport is used as an access port.
Switch ports are used for managing the physical interface and associated Layer 2 protocols and do not handle routing
or bridging. Ports 1–16 on the 35516 are Ethernet ports. The following example demonstrates how to enter the
interface configuration mode for port 16:
Router(config)#
interface eth16
Router(config-if-eth16)#
From the interface configuration mode, use the
switchport
command to configure the access port or the Class of
Service (CoS) default priority for the port.
An access port belongs to and carries the traffic of only one VLAN (see Virtual Interfaces, below.) Traffic is received
and sent in native formats with no VLAN tagging. Traffic arriving on an access port is assumed to belong to the VLAN
assigned to the port. If an access port receives a tagged packet (802.1Q tagged), the packet is dropped, and the
source address is not learned. Static access ports are manually assigned to a VLAN.
Router(config-if-eth16)#
switchport access vlan
<1-4094>
6.1.1 Virtual Interfaces
A virtual interface represents a VLAN of switchports as one interface to the routing or bridging function in the system.
Only one virtual interface can be associated with a VLAN, but it is only necessary to configure a virtual interface for a
VLAN when you wish to route between VLANs or to provide IP host connectivity to the switch. By default, a virtual
interface (veth1) is created for the default VLAN (VLAN 1) to permit remote switch administration. Additional virtual
interfaces must be configured. In Layer 2 mode, virtual interfaces provide IP host connectivity only to the system; in
Layer 3 mode, you can configure routing across virtual interfaces.
In order to create a virtual interface, it must be bound to a VLAN that has already been configured and bound in turn
to a physical port or ports. The following examples show how to create a VLAN (with a VLAN ID of 2), how to select a
port (interface eth9) to belong to the VLAN, and how to create a virtual interface (veth2) by binding it to VLAN 2.