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Creating Ethernet VLANs on Catalyst Switches

Document ID: 10023

Introduction
Prerequisites
Requirements
Components Used
Related Products
Conventions
Difference Between CatOS and Cisco IOS System Software
Configure the VLAN on Catalyst Switches That Run CatOS
Create VLANs and Ports
Remove Ports or VLANs
Troubleshooting Tips
Configure the VLAN on Catalyst 2900XL, 3500XL, 2950, 2970, and 2940 Series
Switches
Create VLANs and Ports
Remove Ports or VLANs
Configure a Multi−VLAN Port on Catalyst 2900XL/3500XL
Configure the VLAN on Catalyst 3550, 3750, 4500/4000, and 6500/6000 Switches That
Run Cisco IOS Software
Create VLANs and Ports
Assign Multiple Ports to a Single VLAN
Remove VLANs
Rename VLANs
How to Isolate the Communiation Between Two VLANs
How to Configure Extended Range VLANs in a Catalyst 6500 Series Switch
Troubleshooting Tips
Verify
Troubleshoot
Inconsistent TLB Value Error on IOS Switches
Recover the vlan.dat File on IOS Switches
Failed to Create VLANs in Extended Range
Failed to Configure VLAN from Startup−Config
Backup and Restore of vlan.dat on Cisco IOS Switches
VLAN Creation Fails with VLAN 1003 parent VLAN missing Error Message
NetPro Discussion Forums − Featured Conversations
Related Information

Introduction
This document provides basic information on how to create VLANs on Catalyst switches that run Catalyst OS
(CatOS) and Cisco IOS® System Software. The sample commands for each section use one Catalyst switch
from each configuration section.

Prerequisites
Requirements
Cisco recommends that you have knowledge of the information in this section.

VLANs are a mechanism to allow network administrators to create logical broadcast domains that can span
across a single switch or multiple switches, regardless of physical proximity. This function is useful to reduce
the size of broadcast domains or to allow groups or users to be logically grouped without the need to be
physically located in the same place.

In order to create VLANs, you must decide how to configure these items:

• What VLAN Trunk Protocol (VTP) domain name and VTP mode to use on this switch
• Which ports on the switch belong to which VLAN
• If you need to have communication between VLANs, or if they are isolated

If you require communication between VLANs, you must use a Layer 3 routing device, such as an
external Cisco router or an internal router module. Here are examples:

♦ WS−X4232−Layer 3 card for Catalyst 4500/4000 Switches with Supervisor Engine I and
Supervisor Engine II
♦ Route Switch Module (RSM) or Route Switch Feature Card (RSFC) for Catalyst 5500/5000
Switches
♦ Multilayer Switch Module (MSM) or Multilayer Switch Feature Card (MSFC) for Catalyst
6500/6000 Switches
Some of the switches have built−in support in software and hardware to do inter−VLAN routing.
With inter−VLAN routing, no external device, modules, or daughter cards are required. Here are
examples of such switches:

♦ Catalyst 3550/3750/6500 with Supervisor Engine 720
♦ Catalyst 4500/4000 with Supervisor Engine II+, Supervisor Engine III, and Supervisor
Engine IV

Refer to these documents for more information on inter−VLAN routing configuration on an MSFC, RSM,
RSFC, or external router:

• Configuring InterVLAN Routing with Catalyst 3750/3560/3550 Series Switches
• Configuring InterVLAN Routing on the MSFC section of Configuring InterVLAN Routing
• Configuring InterVLAN Routing on the RSM section of Configuring InterVLAN Routing
• Configuring InterVLAN Routing on the RSFC
• Configuring InterVLAN Routing on an External Cisco Router section of Configuring InterVLAN
Routing
• Configuring InterVLAN Routing Using an Internal Router (Layer 3 Card) on Catalyst 5500/5000 and
6500/6000 Switches That Run CatOS System Software
• Configuring InterVLAN Routing and ISL/802.1Q Trunking on a Catalyst 2900XL/3500XL/2950
Switch Using An External Router

Note: This document assumes that you have basic connectivity to the switch, either through the console or
through Telnet access. Refer to these documents for more information on how to get basic connectivity to the
switches:

• Catalyst 6500/6000 Series SwitchesBasic Software Configuration
• Catalyst 2900 Series XL SwitchesQuick Start Guide

Components Used
The information in this document is based on these hardware and software versions:

• Catalyst 6009 Switch that runs CatOS 5.5(x) software

• Catalyst 3524XL Switch that runs Cisco IOS Software Release 12.0(5.x)XU
• Catalyst 4507 Switch with Supervisor Engine IV (WS−X4515) that runs Cisco IOS Software Release
12.1(13)EW1

The information in this document was created from the devices in a specific lab environment. All of the
devices used in this document started with a cleared (default) configuration. If your network is live, make sure
that you understand the potential impact of any command.

Related Products
The information in this document can also be used with these switches:

• Catalyst 4500/4000/2948G/2980G/4912G Switches
• Catalyst 5000/2926G Series Switches
• Catalyst 6500/6000 Series Switches
• Catalyst 2900XL/3500XL/2950/3550/3750 Switches

Conventions
Refer to Cisco Technical Tips Conventions for more information on document conventions.

Difference Between CatOS and Cisco IOS System Software
CatOS on the Supervisor Engine and Cisco IOS Software on the MSFC (Hybrid): a CatOS image can be
used as the system software to run the Supervisor Engine on Catalyst 6500/6000 Switches. If the optional
MSFC is installed, a separate Cisco IOS Software image is used to run the MSFC.

Cisco IOS Software on both the Supervisor Engine and MSFC (Native): a single Cisco IOS Software
image can be used as the system software to run both the Supervisor Engine and MSFC on Catalyst
6500/6000 Switches.

Note: Refer to Comparison of the Cisco Catalyst and Cisco IOS Operating Systems for the Cisco Catalyst
6500 Series Switch for more information.

Configure the VLAN on Catalyst Switches That Run CatOS
Create VLANs and Ports
Complete the steps in this section in order to create a VLAN.

Before you can create a VLAN, the switch must be in VTP server mode or VTP transparent mode. If the
switch is a VTP server, you must define a VTP domain name before you can add any VLANs.

1. Define a VTP domain name.

You must define the VTP domain name regardless of:

♦ The number of switches in the network, whether one or many
♦ Whether you use VTP in order to propagate VLANs to other switches in the network
This is the default VTP configuration on the switch:

CatosSwitch> (enable)show vtp domain

2.0. you can use Output Interpreter ( registered customers only) in order to display potential issues and fixes. Domain Name Domain Index VTP Version Local Mode Password −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−−−−− −−−−−−−−−−− −−−−−−−−−−− −−−−−−−−−− 1 2 server − Vlan−count Max−vlan−storage Config Revision Notifications −−−−−−−−−− −−−−−−−−−−−−−−−− −−−−−−−−−−−−−−− −−−−−−−−−−−−− 5 1023 0 disabled Last Updater V2 Mode Pruning PruneEligible on Vlans −−−−−−−−−−−−−−− −−−−−−−− −−−−−−−− −−−−−−−−−−−−−−−−−−−−−−−−− 0.0. there is only a single VLAN for all ports. begin to create VLANs on the switch. Issue the show vlan command in order to display the parameters for all configured VLANs in the administrative domain. You cannot rename or delete VLAN 1. 3. This VLAN is called default. By default.0. Issue the show vtp domain command in order to verify the VTP configuration. After you set and verify the VTP domain.0 disabled disabled 2−1000 Note: If you have the output of a show vtp domain command from your Cisco device. CatosSwitch> (enable)set vtp domain ? <name> Domain name CatosSwitch> (enable)set vtp domain cisco ? mode Set VTP mode passwd Set VTP password pruning Set VTP pruning v2 Set VTP version 2 CatosSwitch> (enable)set vtp domain cisco mode ? client VTP client mode server VTP server mode transparent VTP transparent mode CatosSwitch> (enable)set vtp domain cisco mode server VTP domain cisco modified Note: Refer to Understanding VLAN Trunk Protocol (VTP) for more information on VTP.0.0 disabled disabled 2−1000 Issue the set vtp command in order to set the domain name and mode. CatosSwitch> (enable)show vtp domain Domain Name Domain Index VTP Version Local Mode Password −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−−−−− −−−−−−−−−−− −−−−−−−−−−− −−−−−−−−−− cisco 1 2 server − Vlan−count Max−vlan−storage Config Revision Notifications −−−−−−−−−− −−−−−−−−−−−−−−−− −−−−−−−−−−−−−−− −−−−−−−−−−−−− 5 1023 1 disabled Last Updater V2 Mode Pruning PruneEligible on Vlans −−−−−−−−−−−−−−− −−−−−−−− −−−−−−−− −−−−−−−−−−−−−−−−−−−−−−−−− 0. .

trcrf...1005.2/1−12. decimal_ring_number = 1. mode = (srt. IBM.4095 bridge_number = 0x1. Vlans −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−− −−−−−−− −−−−−−−−−−−−−−−−−−−−−−−− 1 default active 5 1/1−2 3/1−48 4/1−16 1002 fddi−default active 6 1003 token−ring−default active 9 1004 fddinet−default active 7 1005 trnet−default active 8 VLAN Type SAID MTU Parent RingNo BrdgNo Stp BrdgMode Trans1 Trans2 −−−− −−−−− −−−−−−−−−− −−−−− −−−−−− −−−−−− −−−−−− −−−− −−−−−−−− −−−−−− −−−−−− 1 enet 100001 1500 − − − − − 0 0 1002 fddi 101002 1500 − − − − − 0 0 1003 trcrf 101003 1500 − − − − − 0 0 1004 fdnet 101004 1500 − − − − − 0 0 1005 trbrf 101005 1500 − − − ibm − 0 0 VLAN DynCreated RSPAN −−−− −−−−−−−−−− −−−−−−−− 1 static disabled 1002 static disabled 1003 static disabled 1004 static disabled 1005 static disabled VLAN AREHops STEHops Backup CRF 1q VLAN −−−− −−−−−−− −−−−−−− −−−−−−−−−− −−−−−−− 1003 7 7 off a. CatosSwitch> (enable)show vlan VLAN Name Status IfIndex Mod/Ports. Issue the set vlan command in order to create VLANs. state = (active. fddinet. trbrf) said = 1.isolated. auto). fddi..4294967294.18190 pvlan−type = (primary.. Issue the show vlan command in order to verify the VLAN configuration. mtu = 576.13) Set vlan commands: −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− set vlan Set vlan information set vlan mapping Map an 802. translation = 1.0xf. CatosSwitch> (enable)set vlan Usage: set vlan <vlan> <mod/port> (An example of mod/port is 1/1.none) hex_ring_number = 0x1. .community. srb) stp = (ieee....3/1−2.0xfff.32 characters.1q vlan to an Ethernet vlan CatosSwitch> (enable)set vlan 2 name cisco_vlan_2 Vlan 2 configuration successful b.4/1−12) set vlan <vlan_num> [name <name>] [type <type>] [state <state>] [pvlan−type <pvlan_type>] [said <said>] [mtu <mtu>] [ring <hex_ring_number>] [decring <decimal_ring_number>] [bridge <bridge_number>] [parent <vlan_num>] [mode <bridge_mode>] [stp <stp_type>] [translation <vlan_num>] [backupcrf <off|on>] [aremaxhop <hopcount>] [stemaxhop <hopcount>] [rspan] (name = 1.. suspend) type = (ethernet. parent = 2.1005 hopcount = 1..

CatosSwitch> (enable)show vlan VLAN Name Status IfIndex Mod/Ports. For example. CatosSwitch> (enable)set vlan 2 3/1−12 VLAN 2 modified. VLAN Mod/Ports −−−− −−−−−−−−−−−−−−−−−−−−−−− 2 3/1−12 15/1 Note: You can also create the VLAN and add the ports to that VLAN with all the information in a single command. if you want to create the third VLAN and then assign ports 3/13 through 3/15 to that VLAN. VLAN 1 modified. VLAN Mod/Ports −−−− −−−−−−−−−−−−−−−−−−−−−−− 3 3/13−15 15/1 4. Vlans −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−− −−−−−−− −−−−−−−−−−−−−−−−−−−− 1 default active 5 1/1−2 3/1−48 4/1−16 2 cisco_vlan_2 active 75 1002 fddi−default active 6 1003 token−ring−default active 9 1004 fddinet−default active 7 1005 trnet−default active 8 VLAN Type SAID MTU Parent RingNo BrdgNo Stp BrdgMode Trans1 Trans2 −−−− −−−−− −−−−−−−−−− −−−−− −−−−−− −−−−−− −−−−−− −−−− −−−−−−−− −−−−−− −−−−−− 1 enet 100001 1500 − − − − − 0 0 2 enet 100002 1500 − − − − − 0 0 1002 fddi 101002 1500 − − − − − 0 0 1003 trcrf 101003 1500 − − − − − 0 0 1004 fdnet 101004 1500 − − − − − 0 0 1005 trbrf 101005 1500 − − − IBM − 0 0 !−−− Output suppressed. CatosSwitch> (enable)show vlan VLAN Name Status IfIndex Mod/Ports. Vlans −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−− −−−−−−− −−−−−−−−−−−−−−−−−−−−−−−− 1 default active 5 1/1−2 3/16−48 4/1−16 2 cisco_vlan_2 active 75 3/1−12 3 VLAN0003 active 76 3/13−15 1002 fddi−default active 6 1003 token−ring−default active 9 . If you want to add ports to the VLAN. c. VLAN 1 modified. issue the set vlan vlan_number mod/ports command. issue this command: CatosSwitch> (enable)set vlan 3 3/13−15 Vlan 3 configuration successful VLAN 3 modified. Issue the show vlan command in order to verify the VLAN configuration.

Remove Ports or VLANs In order to remove ports from a VLAN. Do you want to continue(y/n) [n]? y Vlan 3 deleted CatosSwitch> (enable)show vlan VLAN Name Status IfIndex Mod/Ports. Vlans −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−− −−−−−−− −−−−−−−−−−−−−−−−−−−−−−−− 1 default active 5 1/1−2 3/16−48 4/1−16 2 cisco_vlan_2 active 75 3/1−12 1002 fddi−default active 6 1003 token−ring−default active 9 1004 fddinet−default active 7 1005 trnet−default active 8 VLAN Type SAID MTU Parent RingNo BrdgNo Stp BrdgMode Trans1 Trans2 −−−− −−−−− −−−−−−−−−− −−−−− −−−−−− −−−−−− −−−−−− −−−− −−−−−−−− −−−−−− −−−−−− 1 enet 100001 1500 − − − − − 0 0 2 enet 100002 1500 − − − − − 0 0 1002 fddi 101002 1500 − − − − − 0 0 1003 trcrf 101003 1500 − − − − − 0 0 1004 fdnet 101004 1500 − − − − − 0 0 1005 trbrf 101005 1500 − − − IBM − 0 0 !−−− Output suppressed. issue the set vlan vlan_number mod/ports command and place the ports in a different VLAN. Issue the clear vlan command in order to delete a VLAN. The switch displays a warning and gives you the opportunity to cancel the current request. Note: Ports 3/13 through 3/15 are not displayed in the output of the show vlan command because the removal of VLAN 3 deactivates these ports. . The ports are not displayed until you add them back in another VLAN. This removal is essentially what happens when you assign a port to any VLAN because all ports initially belong to VLAN 1. and the VLAN no longer exists. 1004 fddinet−default active 7 1005 trnet−default active 8 VLAN Type SAID MTU Parent RingNo BrdgNo Stp BrdgMode Trans1 Trans2 −−−− −−−−− −−−−−−−−−− −−−−− −−−−−− −−−−−− −−−−−− −−−− −−−−−−−− −−−−−− −−−−−− 1 enet 100001 1500 − − − − − 0 0 2 enet 100002 1500 − − − − − 0 0 3 enet 100003 1500 − − − − − 0 0 1002 fddi 101002 1500 − − − − − 0 0 1003 trcrf 101003 1500 − − − − − 0 0 1004 fdnet 101004 1500 − − − − − 0 0 1005 trbrf 101005 1500 − − − IBM − 0 0 !−−− Output suppressed. CatosSwitch> (enable)clear vlan 3 This command will deactivate all ports on vlan 3 in the entire management domain. The ports are deactivated because they remain a part of that VLAN.

The Create VLANs and Ports section provides the procedure. you receive this error message: Cannot add/modify VLANs on a VTP client. In order to correct this. Vlans −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−− −−−−−−− −−−−−−−−−−−−−−−−−−−−−−−− Unable to access VTP Vlan 2 information. In order for the VLAN interface to be fully . you can use Output Interpreter ( registered customers only) in order to display potential issues and fixes. You can either recreate that VLAN or correct the VTP configuration so that the VLAN is reestablished in the VTP domain. CatosSwitch> (enable)show vlan 2 VLAN Name Status IfIndex Mod/Ports. MSM. If you have the output of a show−tech support command from your Cisco device. RSFC. This is sample show port mod/port command output: CatosSwitch> (enable)show port 3/1 Port Name Status Vlan Duplex Speed Type −−−−− −−−−−−−−−−−−−−−−−− −−−−−−−−−− −−−−−−−−−− −−−−−− −−−−− −−−−−−−−−−−− 3/1 inactive 2 auto auto 10/100BaseTX Port AuxiliaryVlan AuxVlan−Status InlinePowered PowerAllocated Admin Oper Detected mWatt mA @42V −−−−− −−−−−−−−−−−−− −−−−−−−−−−−−−− −−−−− −−−−−− −−−−−−−− −−−−− −−−−−−−− 3/1 none none − − − − − !−−− Output suppressed. Refer to Understanding VLAN Trunk Protocol (VTP) for more information on VTP. VLAN AREHops STEHops Backup CRF 1q VLAN −−−− −−−−−−− −−−−−−− −−−−−−−−−− −−−−−−− • The VLAN interfaces created in the routing modules (RSM. This state means that the VLAN to which the ports originally belonged was deleted.Troubleshooting Tips This section provides troubleshooting tips for common problems that you can encounter while you create VLANs on Catalyst switches that run CatOS: • If you create a VLAN when there is no VTP domain name defined. create a VTP domain name on the switch. • Ports are in the inactive state in show port mod/port command output. VLAN Type SAID MTU Parent RingNo BrdgNo Stp BrdgMode Trans1 Trans2 −−−− −−−−− −−−−−−−−−− −−−−− −−−−−− −−−−−− −−−−−− −−−− −−−−−−−− −−−−−− −−−−−− Unable to access VTP Vlan 2 information. you receive this error message: Cannot add/modify VLANs on a VTP server without a domain name. • If you create a VLAN on a switch that is in VTP client mode. Note: A switch can only create VLANs if it is in VTP server mode or VTP transparent mode. or MSFC) come up only when the corresponding VLAN is available in the switch. usually because of VTP. VLAN DynCreated RSPAN −−−− −−−−−−−−−− −−−−−−−− Unable to access VTP Vlan 2 information.

2950. Complete these steps in order to create a VLAN. See the Requirements section of this document for configuration guidelines. Issue the show vlan command in order to check the VLAN information. 2950. begin to create VLANs on the switch. and you can automatically communicate those changes to all the other switches in the network. Fa0/24. Gi0/2 1002 fddi−default active . active. Fa0/4. which means that it is administratively up and line protocol is up. Fa0/22. Fa0/23. Fa0/19. Fa0/8.0. 2970. The default VTP mode on the Catalyst 2900XL. Fa0/16.0. Fa0/10. This VLAN is called default. Fa0/20. there is only a single VLAN for all ports. Fa0/14. Configure the VLAN on Catalyst 2900XL. 3524XL#show vtp status VTP Version : 2 Configuration Revision : 0 Maximum VLANs supported locally : 254 Number of existing VLANs : 5 VTP Operating Mode : Server !−−− This is the default mode. and 2940 Series Switches Create VLANs and Ports Note: The output that you see can be different from some of the command output that this section displays. Fa0/6. Fa0/7. Fa0/3. Fa0/18. with an active device connected to the port. make sure to have at least one port as a member of that VLAN. Fa0/15. and 2940 Switches is the server mode. You cannot rename or delete VLAN 1. Fa0/5. Decide whether to use VTP in your network. With VTP. 3500XL. Gi0/1. VTP Domain Name : VTP Pruning Mode : Disabled VTP V2 Mode : Disabled VTP Traps Generation : Disabled MD5 digest : 0xBF 0x86 0x94 0x45 0xFC 0xDF 0xB5 0x70 Configuration last modified by 0. Fa0/17. Note: Issue the show vtp status command in order to check the VTP status on XL Series Switches. Fa0/2.0 at 0−0−00 00:00:00 2. Fa0/13. 1. you can make configuration changes centrally on a single switch. Fa0/12. Fa0/21. The difference depends on the model of your switch. Fa0/9. Fa0/11. 2970. Refer to Understanding VLAN Trunk Protocol (VTP) for more information on VTP. By default. 3524XL#show vlan VLAN Name Status Ports −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− 1 default active Fa0/1. 3500XL. After you set and verify the VTP domain.

!−−− You can skip this command if the switch is already in server mode and you !−−− want the switch to be in server mode. 3524XL(vlan)#vtp server Device mode already VTP SERVER. Note: A switch can only create VLANs if it is in VTP server mode or VTP transparent mode.10 SAID state Operational state of the VLAN ste Maximum number of Spanning Tree Explorer hops for this VLAN stp Spanning tree characteristics of the VLAN tb−vlan1 ID number of the first translational VLAN for this VLAN (or zero if none) tb−vlan2 ID number of the second translational VLAN for this VLAN (or zero if none) 3524XL(vlan)#vlan 2 name ? WORD The ASCII name for the VLAN 3524XL(vlan)#vlan 2 name cisco_vlan_2 VLAN 2 added: Name: cisco_vlan_2 3524XL(vlan)#exit !−−− You must exit from the VLAN database in order for the changes !−−− to be committed. . Refer to Understanding VLAN Trunk Protocol (VTP) for more information on VTP. 1003 token−ring−default active 1004 fddinet−default active 1005 trnet−default active VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2 −−−− −−−−− −−−−−−−−−− −−−−− −−−−−− −−−−−− −−−−−−−− −−−− −−−−−−−− −−−−−− −−−−−− 1 enet 100001 1500 − − − − − 1002 1003 1002 fddi 101002 1500 − − − − − 1 1003 1003 tr 101003 1500 1005 0 − − srb 1 1002 1004 fdnet 101004 1500 − − 1 IBM − 0 0 1005 trnet 101005 1500 − − 1 IBM − 0 0 Issue this set of commands in privileged mode in order to create another VLAN: 3524XL#vlan database !−−− You must enter into VLAN database in order to configure any VLAN. 524XL(vlan)#vlan ? <1−1005> ISL VLAN index 3524XL(vlan)#vlan 2 ? are Maximum number of All Route Explorer hops for this VLAN backupcrf Backup CRF mode of the VLAN bridge Bridging characteristics of the VLAN media Media type of the VLAN mtu VLAN Maximum Transmission Unit name Ascii name of the VLAN parent ID number of the Parent VLAN of FDDI or Token Ring type VLANs ring Ring number of FDDI or Token Ring type VLANs said IEEE 802.

3524XL# Note: The VTP mode can change from client mode to transparent mode if the switch attempts to learn or pass a greater number of VLANs than it supports. Fa0/8. but the switch only supports one active management VLAN interface at a time and other switched virtual interfaces (SVIs) do not up/up because of Layer 2 functionality. Fa0/12. Switch#configure terminal Switch(config)#interface vlan 2 Switch(config−subif)#management Switch(config−subif)#^Z Switch#show ip interface brief Interface IP−Address OK? Method Status Protocol VLAN1 10.2 YES manual up up FastEthernet0/1 unassigned YES unset up up FastEthernet0/2 unassigned YES unset up up . Fa0/7. you can issue the optional management command under the new SVI in order to automatically shut down VLAN 1 and transfer the IP address to the new VLAN. You must go to interface configuration mode for each of the interfaces that you want to add into the new VLAN. Gi0/2 2 cisco_vlan_2 active 1002 fddi−default active 1003 token−ring−default active 1004 fddinet−default active 1005 trnet−default active VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2 −−−− −−−−− −−−−−−−−−− −−−−− −−−−−− −−−−−− −−−−−−−− −−−− −−−−−−−− −−−−−− −−−−−− 1 enet 100001 1500 − − − − − 1002 1003 2 enet 100002 1500 − − − − − 0 0 1002 fddi 101002 1500 − − − − − 1 1003 1003 tr 101003 1500 1005 0 − − srb 1 1002 1004 fdnet 101004 1500 − − 1 IBM − 0 0 1005 trnet 101005 1500 − − 1 4. Fa0/5. Fa0/13. Fa0/21.0. Fa0/23.. Fa0/10. Fa0/24.0. Fa0/19. Note: You can assign the ports of a Layer 2 Catalyst Switch to multiple VLANs.. Gi0/1. Fa0/16. Issue the show vlan command in order to ensure that the VLAN is created. Fa0/17.0. Fa0/6.2 YES manual up down VLAN2 20. Fa0/14. On a Layer 2 Catalyst Switch. 3. 3524XL#show vlan VLAN Name Status Ports −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− 1 default active Fa0/1. Fa0/3. the switch supports only one active management Layer 3 address.. Therefore.0. Always check that the switches that run in client mode support the same number of VLANs that the switches in server mode send. Exiting. Fa0/2. Fa0/22. Fa0/20. Fa0/15. Fa0/18. You can add ports (interfaces) in the newly created VLAN. Fa0/11. Fa0/4. APPLY completed. Fa0/9.

3524XL(config)#interface fastethernet 0/2 3524XL(config−if)#switchport access ? vlan Set VLAN when interface is in access mode 3524XL(config−if)#switchport access vlan ? <1−1001> VLAN ID of the VLAN when this port is in access mode dynamic When in access mode. Fa0/3 1002 fddi−default active 1003 token−ring−default active 1004 fddinet−default active 1005 trnet−default active VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2 −−−− −−−−− −−−−−−−−−− −−−−− −−−−−− −−−−−− −−−−−−−− −−−− −−−−−−−− −−−−−− −−−−−− 1 enet 100001 1500 − − − − − 1002 1003 2 enet 100002 1500 − − − − − 0 0 . Fa0/4. Building configuration. Fa0/21. 3524XL(config−if)#end 3524XL# 00:55:26: %SYS−5−CONFIG_I: Configured from console by console 3524XL#write memory !−−− This saves the configuration. End with CNTL/Z. Fa0/19. Issue this set of commands in privileged mode in order to add a particular interface in the VLAN: 3524XL#configure terminal Enter configuration commands. Fa0/18. Fa0/22. this interfaces VLAN is controlled by VMPS 3524XL(config−if)#switchport access vlan 2 !−−− These commands assign interface Fast Ethernet 0/2 to VLAN 2. Issue the show vlan command in order to verify the VLAN configuration. Fa0/17. Fa0/5.. !−−− Output suppressed. Fa0/11.. Fa0/14. Fa0/6. Fa0/20. Fa0/7. Fa0/15. Gi0/2 2 cisco_vlan_2 active Fa0/2. 5. Fa0/13. Gi0/1. Fa0/8. Fa0/24. Fa0/16. Fa0/9. Fa0/10. 3524XL(config−if)#exit 3524XL(config)#interface fastethernet 0/3 3524XL(config−if)#switchport access vlan 2 !−−− These commands assign interface Fast Ethernet 0/3 to VLAN 2. Fa0/12. 3524XL#show vlan VLAN Name Status Ports −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− 1 default active Fa0/1. one per line. Fa0/23.

Fa0/15. !−−− Note: Fast Ethernet 0/2 is added back to the default VLAN. Fa0/10. Gi0/2 2 cisco_vlan_2 active Fa0/3 1002 fddi−default active 1003 token−ring−default active 1004 fddinet−default active 1005 trnet−default active VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2 −−−− −−−−− −−−−−−−−−− −−−−− −−−−−− −−−−−− −−−−−−−− −−−− −−−−−−−− −−−−−− −−−−−− 1 enet 100001 1500 − − − − − 1002 1003 2 enet 100002 1500 − − − − − 0 0 1002 fddi 101002 1500 − − − − − 1 1003 1003 tr 101003 1500 1005 0 − − srb 1 1002 1004 fdnet 101004 1500 − − 1 IBM − 0 0 1005 trnet 101005 1500 − − 1 IBM − 0 0 In order to delete the VLAN. issue this set of commands in privileged mode: 3524XL#vlan database . Fa0/8. that port is automatically added back to the default VLAN. Fa0/6. Fa0/2. Fa0/7. After the port is removed from a VLAN that is not VLAN 1 (the default VLAN). 3524XL(config)#interface fastethernet 0/2 3524XL(config−if)#no switchport access vlan 2 !−−− These two commands remove interface Fast Ethernet 0/2 from VLAN 2. Fa0/5. End with CNTL/Z. Fa0/4. Fa0/11. Gi0/1. Fa0/24. Fa0/9. Fa0/22. For example. if you want to remove interface Fast Ethernet 0/2 from cisco_vlan_2 (VLAN 2). Fa0/19. Fa0/23. Fa0/12. Fa0/18. Fa0/20. Fa0/16. Fa0/17. For example. issue the no vlan vlan_number command in VLAN database mode. Interfaces in that VLAN remain a part of that VLAN and are deactivated because they no longer belong to any VLAN. Fa0/13. one per line. if you want to delete cisco_vlan_2 from the switch. 3524XL(config−if)#end 3524XL#show vlan VLAN Name Status Ports −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− 1 default active Fa0/1. issue the no switchport access vlan vlan_number command in interface configuration mode. issue this set of commands in privileged mode: 3524XL#configure terminal Enter configuration commands. Fa0/21. 1002 fddi 101002 1500 − − − − − 1 1003 1003 tr 101003 1500 1005 0 − − srb 1 1002 1004 fdnet 101004 1500 − − 1 IBM − 0 0 1005 trnet 101005 1500 − − 1 IBM − 0 0 Remove Ports or VLANs In order to remove ports from the VLAN. Fa0/14.

Fa0/9.. Gi0/2 1002 fddi−default active 1003 token−ring−default active 1004 fddinet−default active 1005 trnet−default active !−−− Output suppressed. Fa0/13. Fa0/7. Fa0/20. Fa0/16. Fa0/23. 3524XL#show interfaces fastethernet 0/3 FastEthernet0/3 is down. Configure a Multi−VLAN Port on Catalyst 2900XL/3500XL The multi−VLAN port feature on Catalyst 2900XL/3500XL Switches allows you to configure a single port in two or more VLANs. you need to make that interface a Layer 3 interface. Fa0/24. Unless you add the port back in another VLAN. you can use Output Interpreter ( registered customers only) in order to display potential issues and fixes. Fa0/21. Fa0/2. 3524XL#show vlan VLAN Name Status Ports −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− 1 default active Fa0/1. Notice that port Fast Ethernet 0/3 is not displayed in the show vlan command output.. Fa0/11. 3524XL(vlan)#exit APPLY completed. A multi−VLAN port performs normal switching functions . Fa0/8. Deleting VLAN 2.. In the case in this section of the document. Fa0/15. Fa0/19. In order to make the interface usable. you must add interface Fast Ethernet 0/3 to the default VLAN (VLAN 1) in order to make this interface usable. Refer to the Configuring Layer 3 Interfaces section of Configuring Interface Characteristics for more information on Layer 3 interfaces on Catalyst 3550 Switches. Fa0/18.. However. Fa0/10. Fa0/5. Fa0/4. line protocol is down !−−− Output suppressed. 3524XL(vlan)#no vlan 2 !−−− This command removes the VLAN from the database. Fa0/6. Exiting. The removal of VLAN 2 deactivates this port. Fa0/14. you can still use the interface without the addition of the interface to a VLAN. Fa0/17. Note: In the case of Catalyst 3550 Switches. Fa0/12. you must ensure that it belongs to some VLAN. Fa0/22. !−−− This command enters you into the VLAN database mode. This feature allows users from different VLANs to access a server or router without the implementation of inter−VLAN routing capability. If you have the output of a show−tech support command from your Cisco device. the port is neither displayed or usable.. Gi0/1.

Fa0/4 3 VLAN0003 active Fa0/5 4 VLAN0004 active 5 VLAN0005 active 6 VLAN0006 active In the example. Note: These are the limitations to the implementation of multi−VLAN port features: • You cannot configure a multi−VLAN port when a trunk is configured on the switch. This example configures the port that is connected to the router as a multi−VLAN port. three VLANs are created on a Catalyst 3512XL Switch.in all of its assigned VLANs. This feature is not supported on Catalyst 4500/4000. Gi0/2 2 VLAN0002 active Fa0/2. 2. and add assigned VLANs to the multi−VLAN port. and one port of the switch is connected to an external router. and 3 to multi−VLAN port Fast Ethernet 0/1. Fa0/11. port Fast Ethernet 0/1 is connected to an external router. one per line. Configure the Fast Ethernet 0/1 port in multi−VLAN mode.3 !−−− This command assigns VLANs 1. 2950. Fa0/6. You can connect the multi−VLAN port only to a router or server. Fa0/10. 6−3512xl(config−if)#switchport multi vlan ? LINE VLAN IDs of VLANs to be used in multi−VLAN mode add add VLANs to the current list remove remove VLANs from the current list 6−3512xl(config−if)#switchport multi vlan 1. No VTP configuration is necessary. Gi0/1. 3500XL. or 6500/6000 Series Switches or any other Catalyst switches. End with CNTL/Z. VLAN traffic on the multi−VLAN port is not encapsulated as it is in trunking. 1. 2970. Determine which port to configure as a multi−VLAN port. Fa0/7. The switch automatically transitions to VTP transparent mode when the multi−VLAN port feature is enabled. Fa0/8. Fa0/9. Fa0/3. 6−3512xl(config)#interface fastethernet 0/1 6−3512xl(config−if)#switchport mode multi !−−− This command changes the port Fast Ethernet 0/1 mode to multi. 6−3512xl(config−if)#^Z 6−3512xl# . 5500/5000. see the Configure the VLAN on Catalyst 2900XL.2. 6−3512xl#show vlan VLAN Name Status Ports −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−− 1 default active Fa0/1. For more information about how to create VLANs and assign ports to VLANs. Fa0/12. and 2940 Series Switches section of this document. 6−3512xl#configure terminal Enter configuration commands. which disables the VTP. 2. Here. • The multi−VLAN port feature is supported only on Catalyst 2900XL/3500XL Series Switches.

6−3512xl#configure terminal Enter configuration commands. 3 VLAN0003 active Fa0/1. Fa0/7.0 !−−− The management IP address is assigned to VLAN 1. !−−− Now the port is assigned to multiple VLANs 1. 6−3512xl(config)#interface vlan 1 6−3512xl(config−if)#ip address 192.1. 6−3512xl(config−if)#^Z 6−3512xl# 23:56:54: %SYS−5−CONFIG_I: Configured from console by console 6−3512xl#ping 192. 6−3512xl#show interface fastethernet 0/1 switchport Name: Fa0/1 Operational Mode: multi !−−− The port is in multi−VLAN mode. Fa0/10. Fa0/3. or 3. Gi0/1. port Fast Ethernet 0/1 was only in VLAN 1. Issue the show interface interface_id switchport command and the show vlan command in order to verify the configuration.255. and 3. End with CNTL/Z. Gi0/2 2 VLAN0002 active Fa0/1.3. timeout is 2 seconds: . Fa0/4 !−−− Note: Previously. Fa0/5 4 VLAN0004 active 5 VLAN0005 active 4. Issue the ping command from the switch to the router in order to verify the multi−VLAN operation. Fa0/8. The ping command receives a reply from the router each time the management IP address is assigned to any of the VLANs 1.1 255. 2. Fa0/6.168. Fa0/2.1 Type escape sequence to abort. 2.168. one per line. Fa0/1 Fa0/12.1.255.1.1. Sending 5. Administrative Trunking Encapsulation: isl Operational Trunking Encapsulation: isl Negotiation of Trunking: Disabled Access Mode VLAN: 0 ((Inactive)) Trunking Native Mode VLAN: 1 (default) Trunking VLANs Enabled: NONE Pruning VLANs Enabled: NONE Priority for untagged frames: 0 Override vlan tag priority: FALSE Voice VLAN: none Appliance trust: none 6−3512xl#show vlan brief VLAN Name Status Ports −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−− 1 default active Fa0/1. Fa0/9. 100−byte ICMP Echos to 192.168.

6−3512xl(config−if)#shutdown 6−3512xl(config−if)#exit 6−3512xl(config)#interface vlan 2 6−3512xl(config−subif)#ip address 192. one per line. Type escape sequence to abort.0 6−3512xl(config−subif)#no shutdown !−−− The management IP address is assigned to VLAN 2.1. 6−3512xl(config−subif)#exit 6−3512xl(config)#exit 6−3512xl#ping 192. 6−3512xl(config)#interface vlan 2 6−3512xl(config−subif)#no ip address !−−− The management IP address is removed from VLAN 2.1.2 !−−− You can ping the router from VLAN 1.168. End with CNTL/Z. 6−3512xl(config)#interface vlan 1 6−3512xl(config−if)#no ip address !−−− The management IP address is removed from VLAN 1. End with CNTL/Z.1 255.1 Type escape sequence to abort. Sending 5.2.168.1. one per line. 6−3512xl(config−subif)#shutdown . 100−byte ICMP Echos to 192. timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5). timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5). Sending 5.168.1. timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5). round−trip min/avg/max = 1/202/1004 ms 6−3512xl#configure terminal Enter configuration commands. Type escape sequence to abort.168.1. round−trip min/avg/max = 1/1/3 ms 6−3512xl#ping 192. 100−byte ICMP Echos to 192.255.168. 100−byte ICMP Echos to 192. round−trip min/avg/max = 1/2/3 ms 6−3512xl#ping 192. round−trip min/avg/max = 1/1/3 ms 6−3512xl#configure terminal Enter configuration commands.2.1.2 !−−− You can ping the router from VLAN 2.255.168. Sending 5.!!!!! Success rate is 100 percent (5/5).168.1.1.

100−byte ICMP Echos to 192. VLANs that are numbered higher than 1005 are not advertised by VTP. If the switch is a VTP server. the switch must be in VTP server mode or VTP transparent mode.1.dat file. Furthermore.168. You must define a VTP domain name regardless of: • The number of switches in the network.0 6−3512xl(config−subif)#no shut !−−− The management IP address is assigned to VLAN 3.1. round−trip min/avg/max = 1/1/3 ms 6−3512xl#ping 192. 3750.1 255.1. You can create VLANs in either VLAN database mode or global configuration mode. Type escape sequence to abort. timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5). and 6500 Series Switches that run Cisco IOS Software. Refer to the Software Configuration Guide for the switch platform under consideration for VTP configuration information for other Catalyst switch platforms. whether one or many • Whether you use VTP in order to propagate VLANs to other switches in the network Refer to Understanding and Configuring VTP for more information on how to configure VTP on Catalyst 4500/4000 Cisco IOS Software−based Supervisor Engine modules. These other switches include the Catalyst 3550.2 !−−− You can ping the router from VLAN 3.1 Type escape sequence to abort. 4500/4000. timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5). but the configuration tasks also apply to other switches that run Layer 3 (or Cisco IOS Software). 3570. Refer to the LAN Product Support Pages in order to locate the Software Configuration Guide. 100−byte ICMP Echos to 192. The VTP mode must be set to transparent in order to create these VLANs. 6−3512xl(config−subif)#exit 6−3512xl(config)#interface vlan 3 6−3512xl(config−subif)#ip address 192. Sending 5. VLANs that are numbered higher than 1005 are stored in the switch configuration file and not in the VLAN . The default location of the VLAN .1. round−trip min/avg/max = 1/205/1004 ms Configure the VLAN on Catalyst 3550.168.168. You must create VLANs that are numbered higher than 1005 in global configuration mode.1.dat file in Catalyst 4000 Switches with Supervisor Engine IV is the cat4000_flash directory.168. Before you can create a VLAN.2. 6−3512xl(config−subif)#exit 6−3512xl(config)#exit 6−3512xl#ping 192.255.1.255. Sending 5. you must define a VTP domain name before you add any VLANs. Switch#dir cat4000_flash: . and 6500/6000 Switches That Run Cisco IOS Software Create VLANs and Ports This section uses the Catalyst 4500 Switch for sample configuration commands.168.

0 at 5−28−01 05:17:02 Local updater ID is 10. Gi3/4. Gi3/14 Gi3/15.dat 524260 bytes total (523584 bytes free) Note: A Catalyst 6500 Switch that runs Cisco IOS Software allows you to create VLANs in server mode without a VTP domain name. Gi1/2. Gi3/16. The show vtp status command shows the VTP information in the switch. Switch#vlan database . either database mode or global configuration mode. Switch#show vlan VLAN Name Status Ports −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− 1 default active Gi1/1. Gi3/1. Issue the vlan database command in privileged mode in order to enter VLAN database mode. Gi3/18 !−−− Output suppressed. Gi3/12. VLAN Name Status Ports −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− 1002 fddi−default act/unsup 1003 token−ring−default act/unsup 1004 fddinet−default act/unsup 1005 trnet−default act/unsup VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2 −−−− −−−−− −−−−−−−−−− −−−−− −−−−−− −−−−−− −−−−−−−− −−−− −−−−−−−− −−−−−− −−−−−− 1 enet 100001 1500 − − − − − 0 0 1002 fddi 101002 1500 − − − − − 0 0 1003 tr 101003 1500 − − − − − 0 0 1004 fdnet 101004 1500 − − − ieee − 0 0 1005 trnet 101005 1500 − − − ibm − 0 0 Primary Secondary Type Ports −−−−−−− −−−−−−−−− −−−−−−−−−−−−−−−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− 2. Gi3/8.10.0. Enter the correct mode. Gi3/6 Gi3/7. Switch#show vtp status VTP Version : 2 Configuration Revision : 0 Maximum VLANs supported locally : 1005 Number of existing VLANs : 8 VTP Operating Mode : Server VTP Domain Name : cisco VTP Pruning Mode : Enabled VTP V2 Mode : Disabled VTP Traps Generation : Disabled MD5 digest : 0xA4 0x18 0x78 0x52 0x5A 0x1B 0x2E 0x14 Configuration last modified by 0. Gi3/13. Gi3/17. Gi3/2 Gi3/3. Issue the show vlan command in order to check the VLAN information. Gi3/5. Directory of cat4000_flash:/ 1 −rw− 676 <no date> vlan.1 on interface Vl1 (lowest numbered VLAN interface) 1.10. Gi3/9.0. Gi3/10 Gi3/11.

Issue these commands in order to perform the VLAN configuration in global configuration mode: Switch(config)#vlan 3 Switch(config−vlan)#exit Switch(config)# 4.1 no service pad service timestamps debug uptime service timestamps log uptime no service password−encryption service compress−config ! hostname Switch ! ! ip subnet−zero ! spanning−tree extend system−id ! redundancy mode rpr main−cpu auto−sync standard ! ! vlan 2000 ! interface GigabitEthernet1/1 ! interface GigabitEthernet1/2 ! !−−− Output suppressed. Current configuration : 2975 bytes ! version 12. Issue the exit command in order to exit out of VLAN database mode. Note: For the configuration to take effect. Switch#show running−config Building configuration. The end keyword and Ctrl−Z exit methods do not work in VLAN database mode. Switch(vlan)# 3. . Issue the vlan vlan_number command in order to configure a VLAN.. you can either issue the apply command or exit out of VLAN database mode.. Switch(vlan)#vlan 2 VLAN 2 added: Name: VLAN0002 Switch(vlan)#apply APPLY completed. Issue the show run command in order to view VLANs that are numbered higher than 1005 in the running configuration.

if the interface is in Layer 3 mode. The interfaces are Layer 3 interfaces on Catalyst 6500/6000 Series Switches. A mismatch in native VLANs can cause inter−VLAN routing issues. interfaces are in the shutdown state by default. The command to assign an interface to a VLAN is switchport access vlan vlan_number . You can configure the interface as a Layer 2 interface with the switchport command in interface configuration mode. which means that the no switchport command is configured. you cannot assign the interface to a VLAN. Cisco IOS Software interfaces are Layer 2 interfaces on Catalyst 3550. . and 4500 Series Switches. By default. Switch(config−if)#switchport access vlan 2 Switch(config−if)#no shutdown Issue the show interface gigabitethernet module/interface switchport command in order to check the Layer 2 interface status. If you do not explicitly define a native VLAN. the port becomes active if it senses the presence of a physical link. the switchport trunk native vlan command can be useful. In CatOS. VLAN 1 becomes the native VLAN by default. Note: If the interface is configured as a Layer 3 interface.1Q header is not added when data are sent on the native VLAN. Be aware that an IEEE 802. You must issue this command before you assign an interface to a VLAN. In order to associate the ports to VLANs in Cisco IOS Software. 3750. which is a port that can carry more than one VLAN. this minimum configuration is required: Switch(config)#interface gigabitethernet 3/1 Switch(config−if)#switchport !−−− This command is required if the interface is in Layer 3 mode. Ensure that the trunk ports on both of the connected devices have the same native VLAN. Switch#show interface gigabitethernet 3/1 switchport Name: Gi3/1 Switchport: Enabled Administrative Mode: dynamic auto Operational Mode: static access Administrative Trunking Encapsulation: negotiate Operational Trunking Encapsulation: native Negotiation of Trunking: On Access Mode VLAN: 2 (VLAN0002) Trunking Native Mode VLAN: 1 (default) Voice VLAN: none Administrative private−vlan host−association: none Administrative private−vlan mapping: none Administrative private−vlan trunk native VLAN: none Administrative private−vlan trunk encapsulation: dot1q Administrative private−vlan trunk normal VLANs: none Administrative private−vlan trunk private VLANs: none Operational private−vlan: none Trunking VLANs Enabled: ALL Pruning VLANs Enabled: 2−1001 Capture Mode Disabled Capture VLANs Allowed: ALL Voice VLAN: none (Inactive) Appliance trust: none If the port is set up as a trunk. The command is useful if the native VLAN of the interface has been changed or needs to be changed from its defaults.In Cisco IOS Software. The native VLAN is the VLAN that is used if the interface is to become a Layer 2 interface. unlike in CatOS−based switches. among other problems.

1q trunking 1 Port Vlans allowed on trunk Gi3/1 1−4094 Port Vlans allowed and active in management domain Gi3/1 1−4. Switch(config)#interface range fastethernet [mod/slot − mod/slot] 2.3000 Port Vlans in spanning tree forwarding state and not pruned Gi3/1 none If you use the default configuration.1(13)EW and later. The interface range command is supported in Cisco IOS Software Release 12. Switch(config−if−range)#switchport access vlan vlan_number 3. Issue these commands: 1. Switch(config)#interface gigabitethernet 3/1 Switch(config−if)#switchport trunk native vlan 2 Issue this command in order to verify: Switch#show interfaces gigabitethernet 3/1 trunk Port Mode Encapsulation Status Native vlan Gi3/1 on 802. but the neighboring switch has native VLAN 1. Switch#show interfaces gigabitethernet 3/1 trunk Port Mode Encapsulation Status Native vlan Gi3/1 on 802. This example uses the VLAN database mode to remove .2000. issue the no vlan vlan_number command in either VLAN database mode or global configuration mode. In order to change the native VLAN on the interface that is trunking. encapsulation. and trunking VLAN information. issue the switchport trunk native vlan vlan_number command. Issue the show interfaces module/interface trunk command in order to see the native VLAN. the native VLAN is VLAN 2 on one of the switches.This message appears when the native VLAN is mismatched on the two Cisco switches: %CDP−4−NATIVE_VLAN_MISMATCH: Native VLAN mismatch discovered on GigabitEhernet1/1 (2).3000 Port Vlans in spanning tree forwarding state and not pruned Gi3/1 none Assign Multiple Ports to a Single VLAN You can assign the multiple interfaces on a switch to a single VLAN. Remove VLANs In order to remove a VLAN from the VLAN database. Switch(config−if−range)#no shut Note: The interface range command is not supported in all software releases. native VLAN is set to VLAN 1.1q trunking 2 Port Vlans allowed on trunk Gi3/1 1−4094 Port Vlans allowed and active in management domain Gi3/1 1−4. Switch(config−if−range)#switchport mode access 4. with D−R3550−9B GigabitEthernet0/1 (1) In this example message.2000.

one per line. This example uses global configuration mode to rename the VLAN 3: Switch#conf t Enter configuration commands. However. you can issue the show vlan command in order to verify the deletion of the VLAN. it is not necessary to remove the VLAN assigned to the port using the switchport access vlan vlan_number command.. There are two scenarios for when you try to isolate two VLANs. How to Isolate the Communiation Between Two VLANs This section does not discuss private VLANs. This example uses VLAN database mode to rename VLAN 3: Switch#vlan database Switch(vlan)#vlan 3 Switch(vlan)#name CISCO Switch(vlan)#apply APPLY completed. Switch(vlan)#vlan 3 Switch(vlan)#name CISCO In order to verify.VLAN 2. Rename VLANs In order to rename a VLAN from the VLAN database. Switch(vlan)#apply APPLY completed. . Private VLANs provide Layer 2 isolation between ports within the same private VLAN (isolated VLAN) or between the private VLANs (community VLANs). switch#show vlan brief VLAN Name Status Ports −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−− −−−−−−−−−−− 3 CISCO active Fa0/3 Note: When you rename the VLAN. The global configuration mode does not log any message on the console that indicates the deletion of the VLAN. Switch#vlan database Switch(vlan)#no vlan 2 Deleting VLAN 2. issue the name vlan_name command in either VLAN database mode or global configuration mode.. End with CNTL/Z. issue the show vlan brief or show vlan−switch brief command.

This section shows an example of how to isolate the communication between a newly created Layer 3 VLAN and an older VLAN. 4. ACLs are implemented to deny traffic so that VLAN 1 and VLAN 2 cannot communicate with VLAN 5 and so that VLAN 5 does not communicate either . Create the new VLAN in the database.. VLAN 1. Do not set an IP address to the newly created VLANs. subnet mask. and do not set a default gateway. the 3750 switch has two old VLANs (VLAN 1 and VLAN 2). Complete these steps in order to create a Layer 2 VLAN and isolate it from older VLANs: 1. the VLAN becomes a Layer 3 VLAN. Switch#vlan database !−−− You must enter into VLAN database mode in order to !−−− configure any VLAN. In Layer 3 switches. the configuration changes are applied. Assign to each host a static IP address. VLAN 2 and VLAN 5 are Layer 3 VLANs. When you exit vlan database mode. 2. • Layer 2 VLANs • Layer 3 VLANs Isolation Between Two Layer 2 VLANs A Layer 2 VLAN is the VLAN created in the switch and not configured with the interface vlan <vlan_number> command. You can use ACLs to deny communication between the VLANs.. This causes hosts on the ports fa 2/1 and 2/2 to not communicate with each other. 3. Hosts in the different Layer 2 VLANs cannot communicate with each other. Switch(vlan)#vlan 5 VLAN 5 added: Name: VLAN0005 Switch(vlan)#vlan 6 VLAN 6 added: Name: VLAN0006 Switch(vlan)#exit APPLY completed. Make sure the VLAN is created in the vlan database. Isolation Between Two Layer 3 VLANs When you create a VLAN and assign an IP address with the interface vlan <vlan_number> command. The new VLAN must appear in the output of the show vlan command. Devices that belong to one VLAN do not reach anything else but devices within the same VLAN. In this example. Switch(config)#interface fastEthernet 2/1 Switch(config−if)#switchport mode access Switch(config−if)#switchport access vlan 5 Switch(config−if)#no shut witch(config)#interface fastEthernet 2/2 Switch(config−if)#switchport mode access Switch(config−if)#switchport access vlan 6 Switch(config−if)#no shut 5. the hosts between the two VLANs can communicate with each other (if the hosts are configured with the default gateway as the VLAN interface IP address). Exiting. The newly created VLAN is VLAN 5. Configure physical interfaces that connect the clients to the corresponding VLAN..

168.0.0 /24 • VLAN 5 − 192. Set an IP address for the newly created VLAN.16. In this case the new VLAN is VLAN 5. Configure physical interfaces that connect the clients to the corresponding VLAN.0.0 /24 • VLAN 2 − 172.1.0 0.168. Make sure the VLAN is created in the vlan database. the configuration changes are applied. interface VLAN 2 and interface VLAN 5.255 192.0.0.0 0. Switch#configure terminal Switch(config)#access−list 102 deny ip 172.255 any ♦ This access list denies traffic that comes from VLAN 5 to get to VLAN 1 and VLAN 2.255 Switch(config)#access−list 101 permit ip 10. Check the output of the show vlan command.0 0. Switch#vlan database !−−− You must enter into VLAN database mode !−−− in order to configure any VLAN.10.168. Switch(config)#interface fastEthernet 2/1 Switch(config−if)#switchport mode access Switch(config−if)#switchport access vlan 5 Switch(config−if)#no shut You need to configure three access−lists.0.1 255.255 172.0 0.255 192. When you exit vlan database mode.1. Switch#configure terminal Switch(config)#access−list 101 deny ip 10.10.1.0. Switch#configure terminal Switch(config)#interface vlan 1 .1.0 0.10.0. 3. Create the new VLAN in the database.0 0.10.16.16.1.0 Switch(config)#access−list 102 permit ip 172.0.255 10.0.0 0.0 0.10.0 /24 1.255.1..10..255 any And once they are configured.0.with VLAN 1 or VLAN 2.0.0.10.168.1. Exiting. ♦ This access list denies traffic that comes from VLAN 1 to get to VLAN 5. 2.10.0.0 0.0. !−−− Some of the commands in this output are wrapped !−−− to a second line due to spatial reasons.0 0. apply the access lists to interface VLAN 1.0.1.0.168.168.0 Switch(config)#access−list 105 permit ip 192.0 0. Switch(vlan)#vlan 5 VLAN 5 added: Name: VLAN0005 Switch(vlan)#exit APPLY completed.0 Switch(config)#access−list 105 deny ip 192. • VLAN 1 − 10.255.0.0..0.255 any ♦ This access list denies traffic that comes from VLAN 2 to get to VLAN 5.1.1.168.1.0 Switch(config)#no shut 4. Switch(config)#interface vlan 5 Switch(config−if)#ip address 192.16. one for each VLAN. Switch#configure terminal Switch(config)#access−list 105 deny ip 192.

Enter the vtp mode transparent command in configuration mode: Switch(config)#vtp mode transparent 5. Switch(config)# 3. Create the VLAN in configuration mode: Switch(config)#vlan 1311 Notice Switch(config−vlan)#exit 6. End with CNTL/Z. Switch(config−if)#ip access−group 101 in Switch(config−if)#exit Switch#configure terminal Switch(config)#interface vlan 2 Switch(config−if)#ip access−group 102 in Switch(config−if)#exit Switch#configure terminal Switch(config)#interface vlan 5 Switch(config−if)#ip access−group 105 in Switch(config−if)#end How to Configure Extended Range VLANs in a Catalyst 6500 Series Switch In order to configure extended VLANs on the Catalyst 6500 Series Switches running Cisco IOS. one per line. Console into the switch: Switch>enable Switch# 2. Issue the show vlan command in order to check the VLAN information. Switch#show vlan VLAN Name Status Ports −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− 1 default active 101 VLAN0101 active Gi4/8. Gi4/10 1002 fddi−default act/unsup 1003 token−ring−default act/unsup 1004 fddinet−default act/unsup 1005 trnet−default act/unsup 1311 VLAN1311 active VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2 . Enter configuration mode: Switch#configure terminal Enter configuration commands. you need to enter the spanning−tree extend system−id command. Enter the spanning−tree extend system−id command in configuration mode: Switch(config)#spanning−tree extended system−id 4. Then the extended VLAN must be created in the configuration mode and not from the vlan database mode. Complete these steps in order to create extended VLANs on the Catalyst 6500 Series Switches that run Cisco IOS: 1. Exit configuration mode: Switch(config)#exit 7.

The translation bridge (tb) VLANs for VLAN 1. In order for an SVI to come up. it generates this error message: . you can use the switch itself for interVLAN routing. When you try to create any VLAN after this. Troubleshoot Inconsistent TLB Value Error on IOS Switches The inconsistent translational bridging (TLB) value error occurs when you create a VLAN on a Cisco IOS switch that recently received a VTP update from a CatOS switch or which was converted from CatOS. On switches that run Cisco IOS Software. 1002 and 1003 are different in CatOS and are 0 by default . make sure to have at least one port as a member of that VLAN. Ensure that all previous VLANs that were created in VLAN database mode or global configuration mode still exist after the configuration is copied to the switch. Verify There is currently no verification procedure available for this configuration. which means that it is administratively up and line protocol is up. When an SVI is created. the VLAN database is not copied.dat). SVI interfaces show as UP/DOWN in the show ip interface brief command output when the configuration is applied to the switch. it does not automatically create a VLAN in the Layer 2 database. instead of an external router. as the procedure in the Create VLANs and Ports section of this document shows. In order for the SVI to be fully active. This same issue applies when you copy configurations from a different switch or restore configurations with VLANs that were created in VLAN database mode. with an active device connected to the port. The factory default translation bridge VLANs in Cisco IOS switches are: Vlan ID tb1 tb2 −−−−−−−− −−−−− −−−−− 1 1002 1003 1002 1 1003 1003 1 1002 A Cisco IOS switch that recently received a VTP update from a CatOS switch or which was converted from CatOS overwrites the default tb values. This is because CatOS and Cisco IOS have some different default values for translation bridge VLAN. If you copy the configuration from another switch. If the Layer 2 VLAN is not created on the switch. Translational VLANs translate Fiber Distributed Data Interface (FDDI) or Token Ring to Ethernet. a VLAN must be created in VLAN database mode or (in later Cisco IOS Software releases) in global configuration mode. −−−− −−−−− −−−−−−−−−− −−−−− −−−−−− −−−−−− −−−−−−−− −−−− −−−−−−−− −−−−−− −−−−−− 1 enet 100001 1500 − − − − − 0 0 101 enet 100101 1500 − − − − − 0 0 1002 fddi 101002 1500 − − − − − 0 0 1003 tr 101003 1500 − − − − − 0 0 1004 fdnet 101004 1500 − − − ieee − 0 0 1005 trnet 101005 1500 − − − ibm − 0 0 1311 enet 101311 1500 − − − − − 0 0 Troubleshooting Tips This section provides troubleshooting tips for common problems that you can encounter during the creation of VLANs on Catalyst switches that run Cisco IOS Software. or you must recreate the VLANs. You must also replace the VLAN database file (vlan.

Complete these steps in order to recover the vlan. Switch(config)#vlan 50 Switch(config−vlan)#name 50thVLAN Switch(config−vlan)#end Switch# .Exiting.dat file: 1.. If the switch is in VTP Client mode. Fa0/2. VLAN 1002 TLB 1 VLAN 1 has inconsistent TLB values (0 / 0) As a workaround for this issue. Fa0/7.dat. make modifications to the VLAN database at any VTP Server of the same domain. Until the switch is reloaded. Fa0/11. Fa0/8 Fa0/10. Fa0/3. If the vlan. If the switch is in VTP Server or Transparent mode. all the VLANs that were available on the switch are lost. End with CNTL/Z. the VLAN information is on a separate file named vlan. ♦ Delete any VLAN. the VLAN information is present in the switch. Modifications to the VLAN database can be any of these: ♦ Create any VLAN.. ♦ Modify the properties of any existing VLAN.dat File on IOS Switches For Cisco Catalyst Switches that run Cisco IOS software. switch(vlan)#exit APPLY completed. Gi0/1 Gi0/2 10 VLAN0010 active 11 VLAN0011 active 20 VLAN0020 active 21 VLAN0021 active 30 VLAN0030 active 31 VLAN0031 active 40 VLAN0040 active 41 VLAN0041 active 50 Vlan50 active 100 100thVLAN active 2.dat file is deleted accidently and the switch gets reloaded. change the Cisco IOS switch tb default values for VLAN 1. Recover the vlan. Fa0/12. Switch#show vlan VLAN Name Status Ports −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− 1 default active Fa0/1. Switch#configure terminal Enter configuration commands. one per line. Issue the show vlan command in order to confirm the availability of VLAN information. Fa0/6. make any modifications to the VLAN database.. Fa0/4 Fa0/5. 1002 and 1003 to match the CatOS values. switch#vlan data switch(vlan)#no vlan 1002 tb−vlan1 tb−vlan2 switch(vlan)#no vlan 1003 tb−vlan1 tb−vlan2 switch(vlan)#apply APPLY completed.

such as RSPAN. Fallback to use VLAN configuration file from non−volatile memory . The internal VLAN allocation policy is applied only after a reload.bin 7741440 bytes total (65536 bytes free) Failed to Create VLANs in Extended Range % Failed to create VLANs [dec] VLAN(s) not available in Port Manager.EA1a. On trunk ports. In order to display the VLANs used internally.dat file. If a device reload is not an option. Note: Switches that run Catalyst product family software do not support configuration of VLANs 1006−1024.121−22.EA9. use internal VLANs in the extended range. Issue the reload command during a planned maintenance window.121−19. as a workaround. If you configure VLANs 1006−1024. Switch(config)#end Switch#reload Caution: You do not need to issue the reload command immediately.text 6 drwx 4096 Mar 02 1993 03:49:26 html 7 −rwx 3121383 Mar 02 1993 03:47:52 c2950−i6q4l2−mz. Layer 3 LAN ports. which transfers all traffic received in one VLAN to the other VLAN. Refer to the Configuring VLAN Translation section of Configuring VLANs for more information. you can translate one VLAN number to another VLAN number. and some software features. you can use VLAN Translation.dat file. You can configure ascending internal VLAN allocation (from 1006 and up) or descending internal VLAN allocation (from 4094 and down). Issue the show flash: command in order to verify the creation of the vlan. Switch(config)#vlan internal allocation policy {ascending | descending} !−−− Enter the ascending keyword to allocate internal VLANs from 1006 and up. 3.text 3 −rwx 2980487 Mar 02 1993 06:08:14 c2950−i6q4l2−mz. issue the show vlan internal usage command. WAN interfaces and subinterfaces. Switch#show flash: Directory of flash:/ 2 −rwx 5 Mar 01 1993 00:04:47 private−config. the switch automatically creates the vlan. You cannot use an extended range VLAN that is allocated for internal use. ensure that the VLANs do not extend to any switches that run Catalyst product family software. !−−− Enter the descending keyword to allocate internal VLAN from 4094 and down. Failed to Configure VLAN from Startup−Config SW−VLAN−4−BAD−STARTUP−VLAN−CONFIG−FILE: Failed to configure VLAN from startup−config.dat 16 −rwx 1014 Mar 01 1993 00:04:47 config.bin 4 −rwx 1156 Mar 01 1993 01:51:27 vlan. Once any change has been done to the VLAN database.

complete these steps: 1. In order to perform a complete backup of your configuration.dat file.dat file. In order to restore the vlan.dat is empty (0). the problem is that the new VLAN created in the VTP server switch does not propagate to the VTP client switches. complete this step: Copy the vlan.dat file and the configuration file in order to restore the complete configuration. The VLAN configuration is stored in the vlan. copy const_nvram:vlan. Reload the switch. one per line.dat file must be included in the backup with the configuration.dat file resides in non−volatile memory.This message indicates that the VLAN software failed to use the VLAN configuration from the startup configuration file. which creates host connectivity issues. Switch(config)#end Switch# A misconfiguration on a switch can cause the configuration updates of the VTP to fail. it is const_nvram:.dat file from the device's NVRAM to a TFTP server or an external PCMCIA card. Verify if the switch is configured properly for other VTP parameters: .dat. the switch compares the VTP domain name and VTP mode in the startup configuration file and the vlan. When the Supervisor module is replaced.dat file. The network administrator must upload both the vlan. In most cases. If VTP version 2 is enabled. A VTP version 2 capable network device can operate with a network device that runs VTP version 1.dat tftp: Note: The memory location where the vlan. In Cisco Catalyst 6500/6000 Series Switches. If the values do not match.dat is read only during the booting process. Backup and Restore of vlan. Similarily for Catalyst 4500/4000 Switches. Copy the vlan. the switch uses the configuration in the vlan. Every network device in the VTP domain must use the same VTP version. VTP version 2 is disabled by default.dat file. VTP version 1 and VTP version 2 are not interoperable on the network devices in the same VTP domain. as vlan. vlan. A common cause for this issue is a VTP version mismatch between the switches in a VTP domain.dat on Cisco IOS Switches In order to backup the vlan. End with CNTL/Z. The vlan. it is cat4000_flash:. Switch(config)#vlan 102 Switch(config−vlan)#name marketing Switch(config−vlan)#exit VLAN 1003 parent VLAN missing APPLY VLAN changes failed. copy tftp: const_nvram: 2. provided that VTP version 2 is disabled on the VTP version 2 capable network device. VLAN Creation Fails with VLAN 1003 parent VLAN missing Error Message Switch#conf t Enter configuration commands. On bootup. disable it in order to resolve this issue.dat file is stored varies from device to device. the vlan. Refer to the respective product documentation before issuing the copy command. Verify the VTP version that runs on a switch.dat file into the device's NVRAM from a TFTP server or an external PCMCIA card.

The name is case sensitive. Inc. This increments the revision number and forces all VTP clients to update their VLAN database. NetPro Discussion Forums − Featured Conversations for LAN Network Infrastructure: LAN Routing and Switching Network Infrastructure: Getting Started with LANs Related Information • Configuring InterVLAN Routing Using an Internal Router (Layer 3 Card) on Catalyst 5500/5000 and 6500/6000 Switches That Run CatOS System Software • Configuring InterVLAN Routing and ISL/802. In case of a VTP convergence issue. it must be configured on all switches in the domain and the password must be the same. All rights reserved. 5. The featured links are some of the most recent conversations available in this technology.5 • Understanding VLAN Trunk Protocol (VTP) • LAN Product Support • LAN Switching Technology Support • Technical Support & Documentation − Cisco Systems Contacts & Feedback | Help | Site Map © 2007 − 2008 Cisco Systems. • Verify that the switches are connected through trunk links. • Verify that the VTP domain name is exactly the same on the appropriate switches. then the removal of a dummy VLAN on the VTP server. Terms & Conditions | Privacy Statement | Cookie Policy | Trademarks of Cisco Systems. If a password is configured.1Q Trunking on a Catalyst 2900XL/3500XL/2950 Switch Using an External Router • Cisco IOS Desktop Switching Command Reference. Inc. and information about networking solutions. and technologies. NetPro Discussion Forums − Featured Conversations Networking Professionals Connection is a forum for networking professionals to share questions. Updated: Jul 09. where a VTP client does not update the VLAN information. products. because VTP updates are only exchanged over trunk links. suggestions. the workaround is to force a VTP convergence by the creation. Release 12. • Verify that the VTP password is exactly the same on all the switches in the domain. 2007 Document ID: 10023 . The VTP updates are only exchanged between switches in the same VTP domain.0(5)XU • Index − Catalyst 6500 Series Command Reference. The password is case sensitive.