Catalyst 2960-XR Switch VLAN Configuration Guide, Cisco IOS Release 15.0(2)EX1
Configuring VLANs
Configuring VLANs

目次

Configuring VLANs

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to http:/​/​www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

Prerequisites for VLANs

The following are prerequisites and considerations for configuring VLANs:

  • The switch supports 1005 VLANs when running the IP Lite image.

  • The switch supports 256 SVIs when running the IP Lite image.

Restrictions for VLANs

The following are the restrictions for configuring VLANs:

  • The switch supports homogeneous stacking, but does not support mixed stacking.

Information About VLANs

Logical Networks

A VLAN is a switched network that is logically segmented by function, project team, or application, without regard to the physical locations of the users. VLANs have the same attributes as physical LANs, but you can group end stations even if they are not physically located on the same LAN segment. Any switch port can belong to a VLAN, and unicast, broadcast, and multicast packets are forwarded and flooded only to end stations in the VLAN. Each VLAN is considered a logical network, and packets destined for stations that do not belong to the VLAN must be forwarded through a router or a switch supporting fallback bridging. In a switch stack, VLANs can be formed with ports across the stack. Because a VLAN is considered a separate logical network, it contains its own bridge Management Information Base (MIB) information and can support its own implementation of spanning tree.

図 1. VLANs as Logically Defined Networks

VLANs are often associated with IP subnetworks. For example, all the end stations in a particular IP subnet belong to the same VLAN. Interface VLAN membership on the switch is assigned manually on an interface-by-interface basis. When you assign switch interfaces to VLANs by using this method, it is known as interface-based, or static, VLAN membership.

Traffic between VLANs must be routed or fallback bridged.

The switch can route traffic between VLANs by using switch virtual interfaces (SVIs). An SVI must be explicitly configured and assigned an IP address to route traffic between VLANs.

Supported VLANs

The switch supports VLANs in VTP client, server, and transparent modes. VLANs are identified by a number from 1 to 4094. VLAN IDs 1002 through 1005 are reserved for Token Ring and FDDI VLANs. VTP version 1 and version 2 support only normal-range VLANs (VLAN IDs 1 to 1005). In these versions, the switch must be in VTP transparent mode when you create VLAN IDs from 1006 to 4094. VTP version 3 supports the entire VLAN range (VLANs 1 to 4094). Extended range VLANs (VLANs 1006 to 4094) are supported only in VTP version 3. You cannot convert from VTP version 3 to VTP version 2 if extended VLANs are configured in the domain.

The switch or switch stack supports a total of 1005 (normal range and extended range) VLANs. However, the number of routed ports, SVIs, and other configured features affects the use of the switch hardware.

The switch supports per-VLAN spanning-tree plus (PVST+) or rapid PVST+ with a maximum of 128 spanning-tree instances. One spanning-tree instance is allowed per VLAN.

The switch supports IEEE 802.1Q trunking methods for sending VLAN traffic over Ethernet ports.

VLAN Port Membership Modes

You configure a port to belong to a VLAN by assigning a membership mode that specifies the kind of traffic the port carries and the number of VLANs to which it can belong.

When a port belongs to a VLAN, the switch learns and manages the addresses associated with the port on a per-VLAN basis.

表 1 Port Membership Modes and Characteristics

Membership Mode

VLAN Membership Characteristics

VTP Characteristics

Static-access

A static-access port can belong to one VLAN and is manually assigned to that VLAN.

VTP is not required. If you do not want VTP to globally propagate information, set the VTP mode to transparent. To participate in VTP, there must be at least one trunk port on the switch or the switch stack connected to a trunk port of a second switch or switch stack.

Trunk (IEEE 802.1Q) :

  • IEEE 802.1Q— Industry-standard trunking encapsulation.

A trunk port is a member of all VLANs by default, including extended-range VLANs, but membership can be limited by configuring the allowed-VLAN list. You can also modify the pruning-eligible list to block flooded traffic to VLANs on trunk ports that are included in the list.

VTP is recommended but not required. VTP maintains VLAN configuration consistency by managing the addition, deletion, and renaming of VLANs on a network-wide basis. VTP exchanges VLAN configuration messages with other switches over trunk links.

Dynamic access

A dynamic-access port can belong to one VLAN (VLAN ID 1 to 4094) and is dynamically assigned by a VLAN Member Policy Server (VMPS).

The VMPS can be a Catalyst 6500 series switch, for example, but never a Catalyst 2960, 2960-S, or 2960-C switch. The Catalyst 2960, 2960-S, or 2960-C switch is a VMPS client.

You can have dynamic-access ports and trunk ports on the same switch, but you must connect the dynamic-access port to an end station or hub and not to another switch.

VTP is required.

Configure the VMPS and the client with the same VTP domain name.

To participate in VTP, at least one trunk port on the switch or a switch stack must be connected to a trunk port of a second switch or switch stack.

Voice VLAN

A voice VLAN port is an access port attached to a Cisco IP Phone, configured to use one VLAN for voice traffic and another VLAN for data traffic from a device attached to the phone.

VTP is not required; it has no effect on a voice VLAN.

Normal-Range VLAN Overview

Normal-range VLANs are VLANs with VLAN IDs 1 to 1005. If the switch is in VTP server or VTP transparent mode, you can add, modify or remove configurations for VLANs 2 to 1001 in the VLAN database. (VLAN IDs 1 and 1002 to 1005 are automatically created and cannot be removed.)

In VTP versions 1 and 2, the switch must be in VTP transparent mode when you create extended-range VLANs (VLANs with IDs from 1006 to 4094), but these VLANs are not saved in the VLAN database. VTP version 3 supports extended-range VLANs in VTP server and transparent mode.

Configurations for VLAN IDs 1 to 1005 are written to the file vlan.dat (VLAN database), and you can display them by entering the show vlan privileged EXEC command. The vlan.dat file is stored in flash memory. On a switch, the vlan.dat file is stored in flash memory on the stack master. Stack members have a vlan.dat file that is consistent with the stack master.

Token Ring VLANs

Although the switch does not support Token Ring connections, a remote device such as a Catalyst 5000 series switch with Token Ring connections could be managed from one of the supported switches. Switches running VTP Version 2 advertise information about these Token Ring VLANs:

  • Token Ring TrBRF VLANs

  • Token Ring TrCRF VLANs


(注)  


For more information on configuring Token Ring VLANs, see the Catalyst 5000 Series Software Configuration Guide.


Normal-Range VLANs Configuration Process

You configure VLANs in the vlan global configuration command by entering a VLAN ID. Enter a new VLAN ID to create a VLAN, or enter an existing VLAN ID to modify that VLAN. You can use the default VLAN configuration or enter multiple commands to configure the VLAN. For more information about commands available in this mode, see the vlan global configuration command description in the command reference for this release. When you have finished the configuration, you must exit VLAN configuration mode for the configuration to take effect. To display the VLAN configuration, enter the show vlan privileged EXEC command.

VLAN Configuration Saving Process

The configurations of VLAN IDs 1 to 1005 are always saved in the VLAN database (vlan.dat file). If the VTP mode is transparent, they are also saved in the switch running configuration file. You can enter the copy running-config startup-config privileged EXEC command to save the configuration in the startup configuration file. In a switch stack, the whole stack uses the same vlan.dat file and running configuration. To display the VLAN configuration, enter the show vlan privileged EXEC command.

When you save VLAN and VTP information (including extended-range VLAN configuration information) in the startup configuration file and reboot the switch, the switch configuration is selected as follows:

  • If the VTP mode is transparent in the startup configuration, and the VLAN database and the VTP domain name from the VLAN database matches that in the startup configuration file, the VLAN database is ignored (cleared), and the VTP and VLAN configurations in the startup configuration file are used. The VLAN database revision number remains unchanged in the VLAN database.

  • If the VTP mode or domain name in the startup configuration does not match the VLAN database, the domain name and VTP mode and configuration for the VLAN IDs 1 to 1005 use the VLAN database information.

  • In VTP versions 1 and 2, if VTP mode is server, the domain name and VLAN configuration for VLAN IDs 1 to 1005 use the VLAN database information. VTP version 3 also supports VLANs 1006 to 4094.

Normal-Range VLAN Configuration Guidelines

Normal-range VLANs are VLANs with IDs from 1 to 1005. VTP 1 and 2 only support normal-range VLANs.

Follow these guidelines when creating and modifying normal-range VLANs in your network:

  • Normal-range VLANs are identified with a number between 1 and 1001. VLAN numbers 1002 through 1005 are reserved for Token Ring and FDDI VLANs.

  • VLAN configuration for VLANs 1 to 1005 are always saved in the VLAN database. If the VTP mode is transparent, VTP and VLAN configuration are also saved in the switch running configuration file.

  • If the switch is in VTP server or VTP  transparent mode, you can add, modify or remove configurations for VLANs 2 to 1001 in the VLAN database. (VLAN IDs 1 and 1002 to 1005 are automatically created and cannot be removed.)

  • With VTP versions 1 and 2, the switch supports VLAN IDs 1006 through 4094 only in VTP transparent mode (VTP disabled). These are extended-range VLANs and configuration options are limited. Extended-range VLANs created in VTP transparent mode are not saved in the VLAN database and are not propagated. VTP version 3 supports extended range VLAN (VLANs 1006 to 4094) database propagation in VTP server and transparent mode. If extended VLANs are configured, you cannot convert from VTP version 3 to version 1 or 2.

  • 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 or VTP will not function.

  • The switch does not support Token Ring or FDDI media. The switch does not forward FDDI, FDDI-Net, TrCRF, or TrBRF traffic, but it does propagate the VLAN configuration through  VTP.

  • The switch supports 128 spanning tree instances. If a switch has more active VLANs than supported spanning-tree instances, spanning tree can be enabled on 128 VLANs and is disabled on the remaining VLANs. If you have already used all available spanning-tree instances on a switch, adding another VLAN anywhere in the VTP domain creates a VLAN on that switch that is not running spanning-tree. If you have the default allowed list on the trunk ports of that switch (which is to allow all VLANs), the new VLAN is carried on all trunk ports. Depending on the topology of the network, this could create a loop in the new VLAN that would not be broken, particularly if there are several adjacent switches that all have run out of spanning-tree instances. You can prevent this possibility by setting allowed lists on the trunk ports of switches that have used up their allocation of spanning-tree instances.

    If the number of VLANs on the switch exceeds the number of supported spanning-tree instances, we recommend that you configure the IEEE 802.1s Multiple STP (MSTP) on your switch to map multiple VLANs to a single spanning-tree instance.

  • When a switch in a stack learns a new VLAN or deletes or modifies an existing VLAN (either through VTP over network ports or through the CLI), the VLAN information is communicated to all stack members.

  • When a switch joins a stack or when stacks merge, VTP information (the vlan.dat file) on the new switches will be consistent with the active switch.

Extended-Range VLAN Configuration Guidelines

VTP 3 only supports extended-range VLANs. Extended-range VLANs are VLANs with IDs from 1006 to 4094.

Follow these guidelines when creating extended-range VLANs:

  • VLAN IDs in the extended range are not saved in the VLAN database and are not recognized by VTP unless the switch is running VTP version 3.

  • You cannot include extended-range VLANs in the pruning eligible range.

  • In VTP version 1 and 2, a switch must be in VTP transparent mode when you create extended-range VLANs. If VTP mode is server or client, an error message is generated, and the extended-range VLAN is rejected. VTP version 3 supports extended VLANs in server and transparent modes.

  • For VTP version 1 or 2, you can set the VTP mode to transparent in global configuration mode. You should save this configuration to the startup configuration so that the switch boots up in VTP transparent mode. Otherwise, you lose the extended-range VLAN configuration if the switch resets. If you create extended-range VLANs in VTP version 3, you cannot convert to VTP version 1 or 2.

  • STP is enabled by default on extended-range VLANs, but you can disable it by using the no spanning-tree vlan vlan-id global configuration command. When the maximum number of spanning-tree instances are on the switch, spanning tree is disabled on any newly created VLANs. If the number of VLANs on the switch exceeds the maximum number of spanning-tree instances, we recommend that you configure the IEEE 802.1s Multiple STP (MSTP) on your switch to map multiple VLANs to a single spanning-tree instance.

  • Each routed port on the switch creates an internal VLAN for its use. These internal VLANs use extended-range VLAN numbers, and the internal VLAN ID cannot be used for an extended-range VLAN. If you try to create an extended-range VLAN with a VLAN ID that is already allocated as an internal VLAN, an error message is generated, and the command is rejected.

    • Because internal VLAN IDs are in the lower part of the extended range, we recommend that you create extended-range VLANs beginning from the highest number (4094) and moving to the lowest (1006) to reduce the possibility of using an internal VLAN ID.

    • Before configuring extended-range VLANs, enter the show vlan internal usage privileged EXEC command to see which VLANs have been allocated as internal VLANs.

    • If necessary, you can shut down the routed port assigned to the internal VLAN, which frees up the internal VLAN, and then create the extended-range VLAN and re-enable the port, which then uses another VLAN as its internal VLAN.

  • Although the switch or switch stack supports a total of 1005 (normal-range and extended-range) VLANs, the number of routed ports, SVIs, and other configured features affects the use of the switch hardware. If you try to create an extended-range VLAN and there are not enough hardware resources available, an error message is generated, and the extended-range VLAN is rejected.

  • In a switch stack, the whole stack uses the same running configuration and saved configuration, and extended-range VLAN information is shared across the stack.

Default Ethernet VLAN Configuration

The following table displays the default configuration for Ethernet VLANs.


(注)  


The switch supports Ethernet interfaces exclusively. Because FDDI and Token Ring VLANs are not locally supported, you only configure FDDI and Token Ring media-specific characteristics for VTP global advertisements to other switches.


表 2 Ethernet VLAN Defaults and Range

Parameter

Default

Range

VLAN ID

1

1 to 4094.

(注)     

Extended-range VLANs (VLAN IDs 1006 to 4094) are only saved in the VLAN database in VTP version 3.

VLAN name

VLANxxxx, where xxxx represents four numeric digits (including leading zeros) equal to the VLAN ID number

No range

IEEE 802.10 SAID

100001 (100000 plus the VLAN ID)

1 to 4294967294

MTU Size

1500

576-18190

Translational bridge 1

0

0 to 1005

Translational bridge 2

0

0 to 1005

VLAN state

active

active, suspend

Remote SPAN

disabled

enabled, disabled

Private VLANs

none configured

2 to 1001, 1006 to 4094

Default VLAN Configuration

You can change only the MTU size, private VLAN, and the remote SPAN configuration state on extended-range VLANs; all other characteristics must remain at the default state.

How to Configure VLANs

How to Configure Normal-Range VLANs

You can set these parameters when you create a new normal-range VLAN or modify an existing VLAN in the VLAN database:

  • VLAN ID

  • VLAN name

  • VLAN type

    • Ethernet

    • Fiber Distributed Data Interface [FDDI]

    • FDDI network entity title [NET]

    • TrBRF or TrCRF

    • Token Ring

    • Token Ring-Net

  • VLAN state (active or suspended)

  • Maximum transmission unit (MTU) for the VLAN

  • Security Association Identifier (SAID)

  • Bridge identification number for TrBRF VLANs

  • Ring number for FDDI and TrCRF VLANs

  • Parent VLAN number for TrCRF VLANs

  • Spanning Tree Protocol (STP) type for TrCRF VLANs

  • VLAN number to use when translating from one VLAN type to another

You can cause inconsistency in the VLAN database if you attempt to manually delete the vlan.dat file. If you want to modify the VLAN configuration, follow the procedures in this section.

Creating or Modifying an Ethernet VLAN

Each Ethernet VLAN in the VLAN database has a unique, 4-digit ID that can be a number from 1 to 1001. VLAN IDs 1002 to 1005 are reserved for Token Ring and FDDI VLANs. To create a normal-range VLAN to be added to the VLAN database, assign a number and name to the VLAN.


(注)  


With VTP version 1 and 2, if the switch is in VTP transparent mode, you can assign VLAN IDs greater than 1006, but they are not added to the VLAN database.


手順の概要

    1.    configure terminal

    2.    vlan vlan-id

    3.    name vlan-name

    4.    mtu mtu-size

    5.    remote-span

    6.    end

    7.    show vlan {name vlan-name | id vlan-id}


手順の詳細
     コマンドまたはアクション目的
    ステップ 1configure terminal


    例:
    
    Switch# configure terminal
    
    
     

    Enters the global configuration mode.

     
    ステップ 2vlan vlan-id


    例:
    Switch(config)# vlan 20
    
    
     

    Enters a VLAN ID, and enters VLAN configuration mode. Enter a new VLAN ID to create a VLAN, or enter an existing VLAN ID to modify that VLAN.

    (注)     

    The available VLAN ID range for this command is 1 to 4094.

     
    ステップ 3name vlan-name


    例:
    Switch(config-vlan)# name test20
    
    
     

    (Optional) Enters a name for the VLAN. If no name is entered for the VLAN, the default is to append the vlan-id value with leading zeros to the word VLAN. For example, VLAN0004 is a default VLAN name for VLAN 4.

     
    ステップ 4mtu mtu-size


    例:
    Switch(config-vlan)# mtu 256
    
    
     

    (Optional) Changes the MTU size (or other VLAN characteristic).

     
    ステップ 5remote-span


    例:
    Switch(config-vlan)# remote-span
    
    
     

    (Optional) Configures the VLAN as the RSPAN VLAN for a remote SPAN session.

    (注)     

    To return the VLAN name to the default settings, use the no name, no mtu, or no remote-span commands.

     
    ステップ 6end


    例:
    
    Switch(config)# end
    
    
     

    Returns to privileged EXEC mode.

     
    ステップ 7show vlan {name vlan-name | id vlan-id}


    例:
    Switch# show vlan name test20 id 20
    
    
     

    Verifies your entries.

     

    Deleting a VLAN

    When you delete a VLAN from a switch that is in VTP server mode, the VLAN is removed from the VLAN database for all switches in the VTP domain. When you delete a VLAN from a switch that is in VTP transparent mode, the VLAN is deleted only on that specific switch or a switch stack.

    You cannot delete the default VLANs for the different media types: Ethernet VLAN 1 and FDDI or Token Ring VLANs 1002 to 1005.


    注意    


    When you delete a VLAN, any ports assigned to that VLAN become inactive. They remain associated with the VLAN (and thus inactive) until you assign them to a new VLAN.


    手順の概要

      1.    configure terminal

      2.    no vlan vlan-id

      3.    end

      4.    show vlan brief


    手順の詳細
       コマンドまたはアクション目的
      ステップ 1configure terminal


      例:
      
      Switch# configure terminal
      
      
       

      Enters the global configuration mode.

       
      ステップ 2no vlan vlan-id


      例:
      Switch(config)# no vlan 4
      
      
       

      Removes the VLAN by entering the VLAN ID.

       
      ステップ 3end


      例:
      
      Switch(config)# end
      
      
       

      Returns to privileged EXEC mode.

       
      ステップ 4show vlan brief


      例:
      Switch# show vlan brief
      
      
       

      Verifies the VLAN removal.

       

      Assigning Static-Access Ports to a VLAN

      You can assign a static-access port to a VLAN without having VTP globally propagate VLAN configuration information by disabling VTP (VTP transparent mode).

      If you are assigning a port on a cluster member switch to a VLAN, first use the rcommand privileged EXEC command to log in to the cluster member switch.

      If you assign an interface to a VLAN that does not exist, the new VLAN is created.

      手順の概要

        1.    configure terminal

        2.    interface interface-id

        3.    switchport mode access

        4.    switchport access vlan vlan-id

        5.    end

        6.    show running-config interface interface-id

        7.    show interfaces interface-id switchport


      手順の詳細
         コマンドまたはアクション目的
        ステップ 1configure terminal


        例:
        
        Switch# configure terminal
        
        
         

        Enters the global configuration mode.

         
        ステップ 2interface interface-id


        例:
        Switch(config)# interface gigabitethernet2/0/1
        
        
         

        Enters the interface to be added to the VLAN.

         
        ステップ 3switchport mode access


        例:
        Switch(config-if)# switchport mode access
        
        
         

        Defines the VLAN membership mode for the port (Layer 2 access port).

         
        ステップ 4switchport access vlan vlan-id


        例:
        Switch(config-if)# switchport access vlan 2
        
        
         

        Assigns the port to a VLAN. Valid VLAN IDs are 1 to 4094.

        (注)     

        To return an interface to its default configuration, use the default interface interface-id interface configuration command.

         
        ステップ 5end


        例:
        
        Switch(config)# end
        
        
         

        Returns to privileged EXEC mode.

         
        ステップ 6show running-config interface interface-id


        例:
        Switch# copy running-config startup-config
        
        
         

        Verifies the VLAN membership mode of the interface.

         
        ステップ 7show interfaces interface-id switchport


        例:
        Switch# show interfaces gigabitethernet2/0/1
        
        
         

        Verifies your entries in the Administrative Mode and the Access Mode VLAN fields of the display.

         

        How to Configure Extended-Range VLANs

        With VTP version 1 and version 2, when the switch is in VTP transparent mode (VTP disabled), you can create extended-range VLANs (in the range 1006 to 4094). VTP 3 version supports extended-range VLANs in server or transparent move.

        Extended-range VLANs enable service providers to extend their infrastructure to a greater number of customers. The extended-range VLAN IDs are allowed for any switchport commands that allow VLAN IDs.

        With VTP version 1 or 2, extended-range VLAN configurations are not stored in the VLAN database, but because VTP mode is transparent, they are stored in the switch running configuration file, and you can save the configuration in the startup configuration file. Extended-range VLANs created in VTP version 3 are stored in the VLAN database.

        You can change only the MTU size, private VLAN, and the remote SPAN configuration state on extended-range VLANs; all other characteristics must remain at the default state.

        Creating an Extended-Range VLAN

        You create an extended-range VLAN in global configuration mode by entering the vlan global configuration command with a VLAN ID from 1006 to 4094. The extended-range VLAN has the default Ethernet VLAN characteristics and the MTU size, and RSPAN configuration are the only parameters you can change. See the description of the vlan global configuration command in the command reference for the default settings of all parameters. In VTP version 1 or 2, if you enter an extended-range VLAN ID when the switch is not in VTP transparent mode, an error message is generated when you exit VLAN configuration mode, and the extended-range VLAN is not created.

        In VTP version 1 and 2, extended-range VLANs are not saved in the VLAN database; they are saved in the switch running configuration file. You can save the extended-range VLAN configuration in the switch startup configuration file by using the copy running-config startup-config privileged EXEC command. VTP version 3 saves extended-range VLANs in the VLAN database.


        (注)  


        Before you create an extended-range VLAN, you can verify that the VLAN ID is not used internally by entering the show vlan internal usage privileged EXEC command. If the VLAN ID is used internally and you want to free it up, go to the Creating an Extended-Range VLAN with an Internal VLAN ID before creating the extended-range VLAN.


        手順の概要

          1.    configure terminal

          2.    vtp mode transparent

          3.    vlan vlan-id

          4.    mtu mtu size

          5.    remote-span

          6.    end

          7.    show vlan id vlan-id

          8.    copy running-config startup config


        手順の詳細
           コマンドまたはアクション目的
          ステップ 1configure terminal


          例:
          
          Switch# configure terminal
          
          
           

          Enters the global configuration mode.

           
          ステップ 2vtp mode transparent


          例:
          Switch(config)# vtp mode transparent
          
          
           

          Configures the switch for VTP transparent mode, disabling VTP.

          (注)     

          This step is not required for VTP version 3.

           
          ステップ 3vlan vlan-id


          例:
          Switch(config)# vlan 2000
          Switch(config-vlan)#
          
          
           

          Enters an extended-range VLAN ID and enters VLAN configuration mode. The range is 1006 to 4094.

          (注)     

          To delete an extended-range VLAN, use the no vlan vlan-id global configuration command.

           
          ステップ 4mtu mtu size


          例:
          Switch(config-vlan)# mtu 1024
          
          
           

          Modifies the VLAN by changing the MTU size.

           

          ステップ 5remote-span


          例:
          Switch(config-vlan)# remote-span
          
          
           

          (Optional) Configures the VLAN as the RSPAN VLAN.

           
          ステップ 6end


          例:
          
          Switch(config)# end
          
          
           

          Returns to privileged EXEC mode.

           
          ステップ 7show vlan id vlan-id


          例:
          Switch# show vlan id 2000
          
          
           

          Verifies that the VLAN has been created.

           
          ステップ 8copy running-config startup config


          例:
          Switch# copy running-config startup-config
          
          
           

          Saves your entries in the switch startup configuration file.

          To save an extended-range VLAN configuration, you need to save the VTP transparent mode configuration and the extended-range VLAN configuration in the switch startup configuration file. Otherwise, if the switch resets, it will default to VTP server mode, and the extended-range VLAN IDs will not be saved.

          (注)     

          This step is not required for VTP version 3 because VLANs are saved in the VLAN database.

          The procedure for assigning static-access ports to an extended-range VLAN is the same as for normal-range VLANs.

           

          Creating an Extended-Range VLAN with an Internal VLAN ID

          If you enter an extended-range VLAN ID that is already assigned to an internal VLAN, an error message is generated, and the extended-range VLAN is rejected. To manually free an internal VLAN ID, you must temporarily shut down the routed port that is using the internal VLAN ID.

          手順の概要

            1.    show vlan internal usage

            2.    configure terminal

            3.    interface interface-id

            4.    shutdown

            5.    exit

            6.    vtp mode transparent

            7.    vlan vlan-id

            8.    exit

            9.    interface interface-id

            10.    no shutdown

            11.    end

            12.    copy running-config startup config


          手順の詳細
             コマンドまたはアクション目的
            ステップ 1show vlan internal usage


            例:
            Switch# show vlan internal usage
            
            
             

            Displays the VLAN IDs being used internally by the switch. If the VLAN ID that you want to use is an internal VLAN, the display shows the routed port that is using the VLAN ID. Enter that port number in Step 3.

             
            ステップ 2configure terminal


            例:
            Switch# configure terminal
            
            
             

            Enters global configuration mode.

             
            ステップ 3interface interface-id


            例:
            Switch(config)# interface gigabitethernet1/0/3
            
            
             

            Specifies the interface ID for the routed port that is using the VLAN ID, and enters interface configuration mode.

             
            ステップ 4shutdown


            例:
            Switch(config-if)# shutdown
            
            
             

            Shuts down the port to free the internal VLAN ID.

             
            ステップ 5exit


            例:
            Switch(config-if)# exit
            
            
             

            Returns to global configuration mode.

             
            ステップ 6vtp mode transparent


            例:
            Switch(config)# vtp mode transparent
            
            
             

            Sets the VTP mode to transparent for creating extended-range VLANs.

            (注)     

            This step is not required for VTP version 3.

             
            ステップ 7vlan vlan-id


            例:
            Switch(config-vlan)# vlan 2000
            
            
             

            Enters the new extended-range VLAN ID, and enters VLAN configuration mode.

             
            ステップ 8exit


            例:
            Switch(config-vlan)# exit
            
            
             

            Exits from VLAN configuration mode, and returns to global configuration mode.

             
            ステップ 9interface interface-id


            例:
            Switch(config)# interface gigabitethernet1/0/3
            
            
             

            Specifies the interface ID for the routed port that you shut down in Step 4, and enters interface configuration mode.

             
            ステップ 10no shutdown


            例:
            Switch(config)# no shutdown
            
            
             

            Reenables the routed port. It will be assigned a new internal VLAN ID.

             
            ステップ 11end


            例:
            Switch(config)# end
            
            
             

            Returns to privileged EXEC mode.

             
            ステップ 12copy running-config startup config


            例:
            Switch# copy running-config startup-config
            
            
             

            Saves your entries in the switch startup configuration file. To save an extended-range VLAN configuration, you need to save the VTP transparent mode configuration and the extended-range VLAN configuration in the switch startup configuration file. Otherwise, if the switch resets, it will default to VTP server mode, and the extended-range VLAN IDs will not be saved.

            (注)     

            This step is not required for VTP version 3 because VLANs are saved in the VLAN database.

             

            Monitoring VLANs

            表 3 Privileged EXEC show Commands

            Command

            Purpose

            show interfaces [vlan vlan-id]

            Displays characteristics for all interfaces or for the specified VLAN configured on the switch.

            Configuration Examples

            Example: Creating a VLAN Name

            This example shows how to create Ethernet VLAN 20, name it test20, and add it to the VLAN database:

            Switch# configure terminal
            Switch(config)# vlan 20
            Switch(config-vlan)# name test20
            Switch(config-vlan)# end
            
            

            Example: Configuring a Port as Access Port

            This example shows how to configure a port as an access port in VLAN 2:

            Switch# configure terminal
            Enter configuration commands, one per line. End with CNTL/Z.
            Switch(config)# interface gigabitethernet2/0/1
            Switch(config-if)# switchport mode access
            Switch(config-if)# switchport access vlan 2
            Switch(config-if)# end
            
            

            Example: Creating an Extended-Range VLAN

            This example shows how to create a new extended-range VLAN with all default characteristics, enter VLAN configuration mode, and save the new VLAN in the switch startup configuration file:

            Switch(config)# vtp mode transparent
            Switch(config)# vlan 2000
            Switch(config-vlan)# end
            Switch# copy running-config startup config
            
            

            Where to Go Next

            After configuring VLANs, you can configure the following:

            • VLAN Trunking Protocol (VTP)

            • VLAN trunks

            • Private VLANs

            • VLAN Membership Policy Server (VMPS)

            • Tunneling

            • Voice VLANs

            Additional References

            Related Documents

            Related Topic Document Title

            For complete syntax and usage information for the commands used in this chapter.

            Catalyst 2960-XR Switch VLAN Management Command Reference

            Standards and RFCs

            Standard/RFC Title

            MIBs

            MIB MIBs Link

            All supported MIBs for this release.

            To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:

            http:/​/​www.cisco.com/​go/​mibs

            Technical Assistance

            Description Link

            The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies.

            To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds.

            Access to most tools on the Cisco Support website requires a Cisco.com user ID and password.

            http:/​/​www.cisco.com/​support

            Feature History and Information for VLAN

            Release Modification

            Cisco IOS 15.0(2)EX1

            This feature was introduced.