Protocols and standards, Configuring basic vlan settings – H3C Technologies H3C S5560 Series Switches User Manual

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A VLAN tag includes the following fields:

TPID—16-bit tag protocol identifier that indicates whether a frame is VLAN-tagged. By default, the
TPID value 0x8100 identifies a VLAN-tagged frame. A device vendor can set TPID to different
values. For compatibility with a neighbor device, configure the TPID value on the device to be the

same as the neighbor device.

Priority—3-bit long, identifies the 802.1p priority of the frame. For more information, see ACL and
QoS Configuration Guide
.

CFI—1-bit long canonical format indicator that indicates whether the MAC addresses are
encapsulated in the standard format when packets are transmitted across different media.

Available values include:

{

0 (default)—The MAC addresses are encapsulated in the standard format.

{

1—The MAC addresses are encapsulated in a nonstandard format.

This field is always set to 0 for Ethernet.

VLAN ID—12-bit long, identifies the VLAN to which the frame belongs. The VLAN ID range is 0 to
4095. VLAN IDs 0 and 4095 are reserved, and VLAN IDs 1 to 4094 are user configurable.

The way a network device handles an incoming frame depends on whether the frame has a VLAN-tag
and the value of the VLAN tag (if any). For more information, see "

Introduction

."

Ethernet supports encapsulation formats Ethernet II, 802.3/802.2 LLC, 802.3/802.2 SNAP, and 802.3

raw. The Ethernet II encapsulation format is used here. For information about the VLAN tag fields in other

frame encapsulation formats, see related protocols and standards.
For a frame with multiple VLAN tags, the device handles it according to its outer-most VLAN tag and

transmits its inner VLAN tags as the payload.

Protocols and standards

IEEE 802.1Q, IEEE Standard for Local and Metropolitan Area Networks: Virtual Bridged Local Area

Networks

Configuring basic VLAN settings

Step Command

Remarks

1.

Enter system view.

system-view

N/A

2.

(Optional.) Create a
VLAN and enter its view,

or create a list of VLANs.

vlan { vlan-id1 [ to vlan-id2 ] |
all }

By default, only the system default VLAN
(VLAN 1) exists.

3.

Enter VLAN view.

vlan vlan-id

To configure a VLAN after you create a list
of VLANs, you must perform this step.

4.

Configure a name for

the VLAN.

name text

By default, VLAN names are in the format
VLAN vlan-id. For example, the name of
VLAN 100 is VLAN 0100 by default.

5.

Configure the
description of the VLAN. description text

The default setting is VLAN vlan-id, which is

the ID of the VLAN. For example, the
description of VLAN 100 is VLAN 0100 by

default.

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