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CH A P T E R 22

Configuring VTP

This chapter describes how to configure the VLAN Trunking Protocol (VTP) in
Cisco IOS Release 12.2SX.

Note For complete syntax and usage information for the commands used in this chapter, see the Cisco IOS
Master Command List, at this URL:
http://www.cisco.com/en/US/docs/ios/mcl/allreleasemcl/all_book.html

Tip For additional information about Cisco Catalyst 6500 Series Switches (including configuration examples
and troubleshooting information), see the documents listed on this page:
http://www.cisco.com/en/US/products/hw/switches/ps708/tsd_products_support_series_home.html
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This chapter consists of these sections:
• Understanding VTP, page 22-1
• VLAN Interaction, page 22-8
• VTP Default Configuration, page 22-8
• VTP Configuration Guidelines and Restrictions, page 22-9
• Configuring VTP, page 22-10

Understanding VTP
VTP is a Layer 2 messaging protocol that maintains VLAN configuration consistency by managing the
addition, deletion, and renaming of VLANs within a VTP domain. A VTP domain (also called a VLAN
management domain) is made up of one or more network devices that share the same VTP domain name
and that are interconnected with trunks. VTP minimizes misconfigurations and configuration
inconsistencies that can result in a number of problems, such as duplicate VLAN names, incorrect
VLAN-type specifications, and security violations. Before you create VLANs, you must decide whether

Cisco IOS Software Configuration Guide, Release 12.2SX
OL-13013-06 22-1

A network device can be configured to be in one and only one VTP domain. You make global VLAN configuration changes for the domain using either the command-line interface (CLI) or Simple Network Management Protocol (SNMP). page 22-3 • Understanding VTP Advertisements. “Configuring VLANs. The status of the primary and secondary servers is a runtime status and is not configurable.2SX 22-2 OL-13013-06 . page 22-4 • Understanding VTP Version 2. page 22-4 • Understanding VTP Version 3.2(33)SXI. The valid VLAN ranges are as follows: • VTP version 1 and version 2 support VLANs 1 to 1000 only. page 22-6 Understanding the VTP Domain A VTP domain (also called a VLAN management domain) is made up of one or more interconnected network devices that share the same VTP domain name. it inherits the management domain name and the VTP configuration revision number. If you configure the switch as VTP transparent.2(33)SXI and later releases. You can enter the vtp primary privileged EXEC mode command to specify a primary server. VTP version 3 is supported. In Cisco IOS Release 12. With VTP. Note For complete information on configuring VLANs. a VTP server is used to back up the database to the NVRAM and allows you to change the database information. Chapter 22 Configuring VTP Understanding VTP to use VTP in your network. Cisco IOS Software Configuration Guide. In Cisco IOS releases prior to Release 12. • In Cisco IOS Release 12. Release 12. page 22-3 • Understanding VTP Authentication. By default. page 22-2 • Understanding VTP Modes. see Chapter 23. VTP version 3 is supported. A secondary server can only back up the updated VTP configuration received from the primary server in the NVRAMs. there is a VTP-primary server and a VTP-secondary server. • Extended-range VLANs are supported only in VTP version 3. the entire VLAN range is supported (VLANs 1 to 4094).2(33)SXI and later releases. you can create and modify VLANs but the changes affect only the individual switch. The switch ignores advertisements with a different management domain name or an earlier configuration revision number.” These sections describe how VTP works: • Understanding the VTP Domain. If converting from VTP version 3 to VTP version 2. VLANs in the range 1006 to 4094 are removed from VTP control. VTP server mode is the default and the switch is in the no-management domain state until it receives an advertisement for a domain over a trunk link or you configure a management domain. when using VTP version 1 and version 2. If the switch receives a VTP advertisement over a trunk link. page 22-5 • Understanding VTP Pruning. In VTP version 3. In VTP version 3. • The pruning of VLANs still applies to VLANs 1 to 1000 only. A primary server allows you to alter the database information and the database updates sent out are honored by all the devices in the system. all devices come up as secondary servers. you can make configuration changes centrally on one or more network devices and have those changes automatically communicated to all the other network devices in the network.

Cisco IOS Software Configuration Guide. and delete VLANs and specify other configuration parameters (such as VTP version and VTP pruning) for the entire VTP domain.10 SAID values (FDDI). • Transparent—VTP transparent network devices do not participate in VTP. which update their VTP and VLAN configurations as necessary. as well as the following information: • A primary server ID. or delete VLANs on a VTP client. • Emulated LAN names (for ATM LANE). in VTP version 2. Understanding VTP Modes You can configure any one of these VTP modes: • Server—In VTP server mode. VTP advertisements are received by neighboring network devices.2SX OL-13013-06 22-3 . Understanding VTP Advertisements Each network device in the VTP domain sends periodic advertisements out each trunking LAN port to a reserved multicast address. A VTP transparent network device does not advertise its VLAN configuration and does not synchronize its VLAN configuration based on received advertisements. a transparent network device is specific to an instance. If this happens. • Off—In VTP off mode. but you cannot create. you can create. • VTP domain name. the switch cannot be returned to VTP server mode until the NVRAM is functioning. Release 12. • An instance number. • Client—VTP clients behave the same way as VTP servers. • 802. VTP servers advertise their VLAN configuration to other network devices in the same VTP domain and synchronize their VLAN configuration with other network devices based on advertisements received over trunk links. In VTP version 3. Mapping eliminates excessive device administration required from network administrators. • VTP configuration revision number. The following global configuration information is distributed in VTP version 1 and version 2 advertisements: • VLAN IDs (ISL and 802. • Frame format.1Q). the information distributed in VTP version 1 and version 2 advertisements are supported. a network device functions in the same manner as a VTP transparent device except that it does not forward VTP advertisements. Note The VTP server mode automatically changes from VTP server mode to VTP client mode if the switch detects a failure while writing configuration to NVRAM. However. modify. VTP server is the default mode. including the maximum transmission unit (MTU) size for each VLAN. In VTP version 3. • VLAN configuration. Chapter 22 Configuring VTP Understanding VTP VTP maps VLANs dynamically across multiple LAN types with unique names and internal index associations. a transparent network device will forward received VTP advertisements from its trunking LAN ports. change.

a VTP transparent network device inspects VTP messages for the domain name and version and forwards a message only if the version and domain name match. When you configure the authentication password to be hidden. the secret that is used to validate the received VTP updates is visible in plain text in the show commands and the NVRAM file. you must use version 2. VTP version 2 supports the following features not supported in version 1: • Token Ring support—VTP version 2 supports Token Ring LAN switching and VLANs (Token Ring Bridge Relay Function [TrBRF] and Token Ring Concentrator Relay Function [TrCRF]). Note If you are using VTP in a Token Ring environment. The password-string argument is an ASCII string from 1 to 64 characters identifying the administrative domain for the device. you must decide whether to use VTP version 1 or version 2.2SX 22-4 OL-13013-06 . Understanding VTP Authentication In releases prior to Cisco IOS Release 12. • An advertisement request is sent by a Client or a Server in these situations: – On a trunk coming up on a switch with an invalid database. VTP version 2 forwards VTP messages in transparent mode without checking the version. • Unrecognized Type-Length-Value (TLV) Support—A VTP server or client propagates configuration changes to its other trunks. see the “Understanding VLANs” section on page 23-1. – A window size. the secret associated with the password is saved in hexadecimal format in the running configuration. – On all trunks when the database of a switch becomes invalid as a result of a configuration change or a takeover message. Chapter 22 Configuring VTP Understanding VTP • A start index. In the event that a device in a VTP domain is compromised. the administrator had to change the VTP secret across all the devices in the VTP domain. • Version-Dependent Transparent Mode—In VTP version 1. Because only one domain is supported.2(33)SXI. – A start index. VTP version 3 is supported. you can configure the authentication password to be hidden using the vtp password command. – On a specific trunk where a superior database has been advertised. For more information about Token Ring VLANs.dat. In VTP version 3. Instead. it does not appear in plain text in the configuration. even for TLVs that it is not able to parse. – An instance number. • VTP version 3 adds the following fields to the subset advertisement request: – A primary server ID. In Cisco IOS Release 12.2(33)SXI and later releases. Release 12. const_nvram:vlan. Cisco IOS Software Configuration Guide. Understanding VTP Version 2 If you use VTP in your network. The unrecognized TLV is saved in NVRAM.

you must remove the hidden or secret keyword prior to the conversion. The primary-server status is lost when you reload. You can have a working VTP domain without any primary servers. Private VLANs are supported in VTP version 3. These keywords are supported on the Catalyst 6500 series switch only.1s) (MST) database propagation separate from the VLAN database only. or when information is read from NVRAM. Release 12. version 2. Primary and secondary servers may exist on an instance in the domain. The status of the primary and secondary servers is a runtime status and is not configurable. By default. the VLANs in the range 1006 to 4094 are removed from VTP control. The password-string argument is an ASCII string from 1 to 64 characters identifying the administrative domain for the device. The hidden and secret keywords for VTP password are supported only in VTP version 3. VTP version 3 supports Multiple Spanning Tree (802. • VLANs 1002 to 1005 are reserved VLANs in VTP version 1. all devices come up as secondary servers. In the MST database propagation. Cisco IOS Software Configuration Guide. you must use version 2. The secondary servers back up the configuration and continue to propagate the database.2SX OL-13013-06 22-5 . VTP version 3 is supported. When you configure the authentication password to be hidden. or the domain parameters change. switch over. the secret associated with the password is saved in hexadecimal format in the running configuration. VLAN consistency checks (such as VLAN names and values) are performed only when you enter new information through the CLI or SNMP. You can enter the vtp primary privileged EXEC mode command to specify a primary server. In Cisco IOS Release 12. If the digest on a received VTP message is correct. A secondary server can only back up the updated VTP configuration received from the primary server in the NVRAMs. If converting to VTP version 2 from VTP version 3. Chapter 22 Configuring VTP Understanding VTP • Consistency Checks—In VTP version 2. VTP version 3 also supports the following features not supported in version 1 and version 2: • Enhanced authentication—In VTP version 3. A primary server allows you to alter the database information. Consistency checks are not performed when new information is obtained from a VTP message. a VTP server is used to back up the database to the NVRAM and allows you to change the database information. If you convert from VTP version 3 to VTP version 2. the entire VLAN range is supported (VLANs 1 to 4094). Note In Cisco IOS Release 12. The pruning of VLANs still applies to VLANs 1 to 1000 only. and version 3.2(33)SXI and later releases. • Support for propagation of any database in a domain—In VTP version 1 and version 2. • Support for extended range VLAN database propagation—VTP version 1 and version 2 support VLANs 1 to 1000 only. there is a VTP primary server and a VTP econdary server. Instead. its information is accepted without consistency checks. VTP version 3 supports all the features in version 1 and version 2.2(33)SXI and later releases. The primary-server status is needed only when database changes have to be performed and is obtained when the administrator issues a takeover message in the domain. and the database updates sent out are honored by all the devices in the system. it does not appear in plain text in the configuration. In VTP version 3. Extended-range VLANs are supported in VTP version 3 only. Understanding VTP Version 3 Note If you are using VTP in a Token Ring environment. you can configure the authentication password to be hidden using the vtp password command.

Unlike the per-port configuration. unknown. • CLI to turn off/on VTP on a per-trunk basis—You can enable VTP on a per-trunk basis using the vtp interface configuration mode command. and every network device in the network receives it. you must manually configure the VLANs allowed on trunks. Interface 1 on network Switch 1 and port 2 on Switch 4 are assigned to the Red VLAN. there is no longer a restriction to propagate only VLAN database information. multicast. On devices that do not support VTP pruning. You can disable VTP on a per-trunk basis using the no form of this command. You enable pruning globally on the switch (see the “Enabling VTP Pruning” section on page 22-13). such as broadcast. you can specify the OFF option on a per-VTP instance basis. A broadcast is sent from the host connected to Switch 1. the system could be configured as VTP-server for the VLAN database and as VTP-off for the MST database. You can use VTP version 3 to propagate any database information across the VTP domain. Release 12. When you disable VTP on the trunking port. VTP pruning is disabled. For VTP pruning to be effective. all devices in the management domain must support VTP pruning. Cisco IOS Software Configuration Guide. In VTP version 3. For example. You configure pruning on Layer 2 trunking LAN ports (see the “Configuring a Layer 2 Switching Port as a Trunk” section on page 17-10). when you enable or disable pruning. Chapter 22 Configuring VTP Understanding VTP In VTP version 3. In VTP versions 1 and 2. the domain administrator must manually enable or disable VTP pruning explicitly on each device. Switch 1 floods the broadcast. Figure 22-1 shows a switched network without VTP pruning enabled. and 6 have no ports in the Red VLAN. VTP pruning increases available bandwidth by restricting flooded traffic to those trunk links that the traffic must use to access the appropriate network devices. 5. and flooded unicast packets. this applies to all the trunking ports in the system.2SX 22-6 OL-13013-06 . MST updates are sent out on the trunk ports in the system. VLAN databases are propagated by VTP. VTP on a global basis—When you set VTP mode to OFF globally. it is propagated to the entire domain and accepted by all the devices in that domain. Two VTP version 3 regions can only communicate over a VTP version 1 or VTP version 2 region in transparent mode. Understanding VTP Pruning VTP pruning enhances network bandwidth use by reducing unnecessary flooded traffic. You will not be provided with the option of setting VTP to OFF for the MST database and ON for the VLAN database. By default. and the MST updates received by the system are discarded. even though Switches 3. In this case. A separate instance of the protocol is running for each application that uses VTP. all the VTP instances for that port are disabled.

2SX OL-13013-06 22-7 . and 6 because traffic for the Red VLAN has been pruned on the links indicated (port 5 on Switch 2 and port 4 on Switch 4). By default. Release 12. You can set VLAN pruning eligibility when VTP pruning is enabled or disabled for the VTP domain. VLAN 1 is always pruning ineligible. traffic from VLAN 1 cannot be pruned.Chapter 22 Configuring VTP Understanding VTP Figure 22-1 Flooding Traffic without VTP Pruning Catalyst series Switch 4 Interface 2 Catalyst series Catalyst series Switch 5 Switch 2 Red VLAN Interface 1 31074 Catalyst series Catalyst series Catalyst series Switch 6 Switch 3 Switch 1 Figure 22-2 shows the same switched network with VTP pruning enabled. VTP pruning operates when a LAN port is trunking. use the switchport trunk pruning vlan command (see the “Configuring a Layer 2 Switching Port as a Trunk” section on page 17-10). when any given VLAN exists or not. VTP pruning takes effect several seconds after you enable it. VLANs 2 through 1000 are pruning eligible. 5. To configure VTP pruning on a trunking LAN port. Figure 22-2 Flooding Traffic with VTP Pruning Switch 4 Interface 2 Interface 4 Flooded traffic is pruned. Switch 2 Red VLAN Switch 5 Interface 5 Interface 1 31075 Switch 6 Switch 3 Switch 1 Enabling VTP pruning on a VTP server enables pruning for the entire management domain. VTP pruning does not prune traffic from pruning-ineligible VLANs. and when the LAN port is currently trunking or not. Cisco IOS Software Configuration Guide. The broadcast traffic from Switch 1 is not forwarded to Switches 3.

2SX 22-8 OL-13013-06 . the VTP version 3 device continues to send VTP version 3 packets in addition to VTP version 3 device 2 packets. Release 12. MST database mode Transparent Cisco IOS Software Configuration Guide. VTP version 1-only capable devices cannot interoperate with VTP version 3 devices. it will be configured as a VTP version 2 device if VTP version 2 conflicts do not exist. the VTP version 3 device stops transmitting VTP version 2 packets on that trunk port. VTP version 3 sends VTP version 3 and VTP version 2 updates on VTP version 2-detected trunks. the VTP version 1 or 2 VLAN database mode is carried over to VTP version 3 VLAN database mode. Chapter 22 Configuring VTP VLAN Interaction VLAN Interaction This section describes the VLAN interaction between devices with different VTP versions: • Interaction Between VTP Version 3 and VTP Version 2 Devices. when you configure the VTP version to be version 3. the VTP version 3 device sends a scaled-down version of the VLAN database on that particular trunk in a VTP version 2 format. If the VTP version 3 device does not receive VTP version 2 packets for an interval of time on the trunk port. For example. to allow two kinds of neighbors to coexist on the trunk. page 22-8 Interaction Between VTP Version 3 and VTP Version 2 Devices When a VTP version 3 device on a trunk port receives messages from a VTP version 2 device. VTP Default Configuration Table 22-1 shows the default VTP configuration. A VTP version 3 device does not accept configuration from a VTP version 2 (or VTP version 1) device. Unlike in VTP version 2. version 3 does not configure all the VTP version 3-capable devices in the domain to start behaving as VTP version 3 systems. page 22-8 • Interaction Between VTP Version 3 and VTP Version 1 Devices. Table 22-1 VTP Default Configuration Feature Default Value VTP domain name Null VTP version 1 and version 2 mode Server VTP version 3 mode The VTP version 3 VLAN database mode is the same as the VLAN database mode in VTP version 1 or 2 after the conversion from VTP version 1 or 2 to VTP version 3. Even when a VTP version 3 device detects a VTP version 2 device on a trunk port. A VTP version 3 device does not send out VTP version 2-formatted packets on a trunk port unless it first receives VTP version 2 packets on that trunk. Interaction Between VTP Version 3 and VTP Version 1 Devices When a VTP version 1 device that is capable of VTP version 2 or VTP version 3 receives a VTP version 3 packet.

• When you enable or disable VTP pruning on a VTP server. • You must configure a password on each network device in the management domain when in secure mode. enter the no vtp file command to return to the default configuration. You cannot configure pruning eligibility separately for each trunk.Chapter 22 Configuring VTP VTP Configuration Guidelines and Restrictions Table 22-1 VTP Default Configuration (continued) Feature Default Value VTP version 3 server type Secondary VTP version 2 state Version 2 is disabled VTP password None VTP pruning Disabled VTP Configuration Guidelines and Restrictions When implementing VTP in your network. • A VTP version 2-capable network device can operate in the same VTP domain as a network device that runs VTP version 1 if VTP version 2 is disabled on the VTP version 2-capable network device (VTP version 2 is disabled by default). not on all network devices in the VTP domain. all of the version 2-capable network devices in the domain enable VTP version 2. • All network devices in a VTP domain must run the same VTP version.2SX OL-13013-06 22-9 . You must configure extended-range VLANs manually on each network device. the VLANs in the range 1006 to 4094 are removed from VTP control. • Before installing a redundant supervisor engine. you must enable VTP version 2 for Token Ring VLAN switching to function properly. • VTP version 1 and VTP version 2 do not propagate configuration information for extended-range VLANs (VLAN numbers 1006 to 4094). • The pruning-eligibility configuration applies globally to all trunks on the switch. • In a Token Ring environment. follow these guidelines and restrictions: • Supervisor engine redundancy does not support nondefault VLAN data filenames or locations. If you convert from VTP version 3 to VTP version 2. Do not enter the vtp file file_name command on a switch that has a redundant supervisor engine. the management domain will not function properly if you do not assign a management domain password to each network device in the domain. • VTP version 3 supports extended-range VLANs (VLAN numbers 1006 to 4094). When you enable VTP version 2 on a network device. • VTP version 3 supports propagation of any database in a domain by allowing you to configure a primary and secondary server. Cisco IOS Software Configuration Guide. • Do not enable VTP version 2 on a network device unless all of the network devices in the same VTP domain are version 2-capable. VTP pruning for the entire management domain is enabled or disabled. • When you configure VLANs as pruning eligible or pruning ineligible. pruning eligibility for those VLANs is affected on that switch only. Release 12. Caution If you configure VTP in secure mode.

• Prior to configuring VTP version 3. Cisco IOS Software Configuration Guide. see the “Configuring the List of Prune-Eligible VLANs” section on page 17-14. perform this task: Command Purpose Router(config)# vtp password password-string Sets a password. page 22-14 Note You can enter the VTP global parameters in either global configuration mode or in EXEC mode. Configuring VTP Version 1 and Version 2 Passwords To configure the VTP version 1 and version 2 global parameters. page 22-11 • Enabling VTP Pruning.2(33)SXI and later releases. Release 12. page 22-18 Configuring VTP Global Parameters These sections describe configuring the VTP global parameters: • Configuring VTP Version 1 and Version 2 Passwords. you must ensure that the spanning-tree extend system-id command has been enabled. page 22-15 • Configuring VTP Mode on a Per-Port Basis. Chapter 22 Configuring VTP Configuring VTP • In Cisco IOS Release 12. page 22-17 • Displaying VTP Statistics. which can be from 1 to 64 characters long. the network administrator has to manually configure VTP version 3 on the switches that need to run VTP version 3.2SX 22-10 OL-13013-06 . the VTP mode changes to transparent. page 22-13 • Enabling VTP Version 3. page 22-13 • Enabling VTP Version 2. configure the VLANs that are used by the transparent-mode network devices or that need to be carried across trunks as pruning ineligible. Router(config)# no vtp password Clears the password. for the VTP domain. page 22-10 • Configuring VTP Version 3 Password. For information about configuring prune eligibility. On trunk connections to network devices in VTP transparent mode. page 22-10 • Configuring the VTP Mode. • If there is insufficient DRAM available for use by VTP. • VTP version 3 is not supported on private VLAN (PVLAN) ports. Configuring VTP These sections describe how to configure VTP: • Configuring VTP Global Parameters. • Network devices in VTP transparent mode do not send VTP Join messages.

perform this task: Command Purpose Router(config)# vtp password password-string [hidden Configures a password. the password-string must be entered in 32-digit hexadecimal format. Router# Note If you configure a VTP password in EXEC mode. Release 12. Router(config)# no vtp password Clears the password. the password is not stored in the running-config file. Router# Note The password is not stored in the running-config file. This example shows one way to configure the password with a hidden key saved in hexadecimal format in the running configuration: Router# configure terminal Router(config)# vtp password 82214640C5D90868B6A0D8103657A721 hidden Setting device VTP password Router# This example shows how you configure the password secret key in hexadecimal format: Router# configure terminal Router(config)# vtp password 300F060A2B0601035301020107010201 secret Setting device VTP password Router# Cisco IOS Software Configuration Guide. Note When entering the secret keyword.2SX OL-13013-06 22-11 . This example shows one way to configure a VTP password in global configuration mode: Router# configure terminal Router(config)# vtp password water Setting device VTP database password to water. Router# This example shows how to configure a VTP password in EXEC mode: Router# vtp password WATER Setting device VLAN database password to WATER. for the VTP domain. Chapter 22 Configuring VTP Configuring VTP This example shows one way to configure a VTP password in global configuration mode: Router# configure terminal Router(config)# vtp password WATER Setting device VLAN database password to WATER. which can be from 1 to 64 characters | secret] long or in 32-digit hexadecimal format. Configuring VTP Version 3 Password To configure the VTP version 3 password.

00b8.1400 1 stp7 Do you want to continue (y/n) [n]? y Router# Cisco IOS Software Configuration Guide. Step 2 Router# show vtp status Verifies the configuration.---. This example shows how to configure this device as the primary server if the password feature is disabled: Router# vtp primary This system is becoming primary server for feature vlan No conflicting VTP version 3 devices found. The vtp primary command does not have a no form.-------------.2SX 22-12 OL-13013-06 . • Switchover between redundant supervisors. • Takeover from another server. domain password). • Any domain configuration change (version. Do you want to continue? [confirm]y Router# This example shows how to force this device to be the primary server for the VTP MST feature when the domain VTP password is set with the hidden or secret keyword: Router# vtp primary mst force Enter VTP password: water1 This switch is becoming Primary server for mst feature in the VTP domain VTP Database Conf Switch ID Primary Server Revision System Name -----------.1400=00d0. Release 12. Chapter 22 Configuring VTP Configuring VTP Configuring VTP Version 3 Server Type To specify a primary server.-------------. Do you want to continue? [confirm]y Router# This example shows how to configure this device as the primary server for the VTP VLAN feature if the password feature is disabled: Router# vtp primary vlan This system is becoming primary server for feature vlan No conflicting VTP version 3 devices found.00b8. perform this task: Command Purpose Step 1 Router# vtp primary [vlan | mst] [force] Configure this device as the primary server. one of the following conditions must be met: • System reload. domain name. Do you want to continue? [confirm]y Router# This example shows how to force this device to be the primary server for the VTP MST feature if the password feature is disabled: Router# vtp primary mst force This system is becoming primary server for feature MST No conflicting VTP version 3 devices found.-------------------- VLANDB Yes 00d0. • Change in the mode configuration.-------. To return to the secondary server status.

When you enable VTP version 2 on a network device. Chapter 22 Configuring VTP Configuring VTP Enabling VTP Pruning To enable VTP pruning in the management domain. Note In a Token Ring environment. Cisco IOS Software Configuration Guide. Release 12. This example shows one way to enable VTP pruning in the management domain: Router# configure terminal Router(config)# vtp pruning Pruning switched ON This example shows how to enable VTP pruning in the management domain with any release: Router# vtp pruning Pruning switched ON This example shows how to verify the configuration: Router# show vtp status | include Pruning VTP Pruning Mode: Enabled Router# For information about configuring prune eligibility. Step 2 Router# show vtp status Verifies the configuration. Every network device in the VTP domain must use the same VTP version. Router(config)# no vtp version Reverts to the default (VTP version 1).2SX OL-13013-06 22-13 . perform this task: Command Purpose Step 1 Router(config)# vtp pruning Enables VTP pruning in the management domain. see the “Configuring the List of Prune-Eligible VLANs” section on page 17-14. every VTP version 2-capable network device in the VTP domain enables version 2. perform this task: Command Purpose Step 1 Router(config)# vtp version {1 | 2} Enables VTP version 2. Router(config)# no vtp pruning Disables VTP pruning in the management domain. Enabling VTP Version 2 VTP version 2 is disabled by default on VTP version 2-capable network devices. you must enable VTP version 2 for Token Ring VLAN switching to function properly on devices that support Token Ring interfaces. Do not enable VTP version 2 unless every network device in the VTP domain supports version 2. Step 2 Router# show vtp status Verifies the configuration. To enable VTP version 2. Caution VTP version 1 and VTP version 2 are not interoperable on network devices in the same VTP domain.

To enable VTP version 3. Note Prior to configuring VTP version 3. Router(config)# no vtp version Reverts to the default (VTP version 1). Router(config)# This example shows how to enable VTP version 2 with any release: Router# vtp version 2 V2 mode enabled. perform this task: Command Purpose Step 1 Router(config)# vtp version 3 Enables VTP version 3. This example shows one way to enable VTP version 3: Router# configure terminal Router(config)# vtp version 3 Router(config)# This example shows how to verify the configuration: Router# show vtp status VTP Version capable : 1 to 3 VTP version running : 3 VTP Domain Name : lab_switch VTP Pruning Mode : Disabled VTP Traps Generation : Disabled Device ID : 0015.0040 Feature VLAN: -------------- Cisco IOS Software Configuration Guide. both the primary and secondary servers may exist on an instance in the domain. In Cisco IOS Release 12.2(33)SXI and later releases. Router# This example shows how to verify the configuration: Router# show vtp status | include V2 VTP V2 Mode: Enabled Router# Enabling VTP Version 3 VTP version 3 is disabled by default. You can enable version 3 in global configuration mode only.2SX 22-14 OL-13013-06 . you must ensure that the spanning-tree extend system-id command has been enabled. Caution In VTP version 3. Release 12. Step 2 Router# show vtp status Verifies the configuration. Chapter 22 Configuring VTP Configuring VTP This example shows one way to enable VTP version 2: Router# configure terminal Router(config)# vtp version 2 V2 mode enabled.c724. the network administrator has to manually configure VTP version 3 on the switches that need to run VTP version 3.

Step 3 Router(config)# end Exits VLAN configuration mode. Router(config)# vtp domain lab_network Setting VTP domain name to lab_network Router(config)# end Router# This example shows how to configure the switch as a VTP client: Router# configuration terminal Router(config)# vtp mode client Cisco IOS Software Configuration Guide. the switch learns the domain name from the VTP server in the domain. transparent | off} {vlan | mst | unknown} Step 2 Router(config)# vtp domain domain-name (Optional for server mode) Defines the VTP domain name. If the switch has a trunk connection to a VTP domain. Chapter 22 Configuring VTP Configuring VTP VTP Operating Mode : Server Number of existing VLANs : 6 Number of existing extended VLANs : 0 Configuration Revision : 0 Primary ID : 0000.0000 Primary Description : MD5 digest : 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 Feature MST: -------------- VTP Operating Mode : Transparent Feature UNKNOWN: -------------- VTP Operating Mode : Transparent Router# Configuring the VTP Mode To configure the VTP mode. Step 4 Router# show vtp status Verifies the configuration.2SX OL-13013-06 22-15 . Note When VTP is disabled. you can enter VLAN configuration commands in configuration mode instead of the VLAN database mode and the VLAN configuration is stored in the startup configuration file.0000. VTP server mode requires a domain name. Note You cannot clear the domain name. which can be up to 32 characters long. Release 12. perform this task: Command Purpose Step 1 Router(config)# vtp mode {client | server | Configures the VTP mode. This example shows how to configure the switch as a VTP server: Router# configuration terminal Router(config)# vtp mode server Setting device to VTP SERVER mode.

Router(config)# end Router# This example shows how to disable VTP on the switch and to disable VTP advertisement forwarding: Router# config terminal Enter configuration commands. Release 12.0040 Feature VLAN: -------------- VTP Operating Mode : Server Number of existing VLANs : 6 Number of existing extended VLANs : 0 Configuration Revision : 0 Primary ID : 0000.2SX 22-16 OL-13013-06 .0000 Primary Description : MD5 digest : 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 Feature MST: -------------- VTP Operating Mode : Transparent Feature UNKNOWN: -------------- VTP Operating Mode : Transparent Router# Cisco IOS Software Configuration Guide.0000. End with CNTL/Z.c724. one per line. Router(config)# exit Router# This example shows how to verify the configuration: Router# show vtp status VTP Version capable : 1 to 3 VTP version running : 3 VTP Domain Name : lab_network VTP Pruning Mode : Disabled VTP Traps Generation : Disabled Device ID : 0015. Router(config)# vtp mode off Setting device to VTP OFF mode. Chapter 22 Configuring VTP Configuring VTP Setting device to VTP CLIENT mode. Router(config)# exit Router# This example shows how to disable VTP on the switch: Router# configuration terminal Router(config)# vtp mode transparent Setting device to VTP TRANSPARENT mode.

you can configure VTP mode on a per-port basis. With Release 12. Incoming and outgoing vtp pdus are blocked. Step 3 Router(config-if)# end Exits interface configuration mode. or tengigabitethernet This example shows how to configure VTP mode on a port: Router# config terminal Enter configuration commands. Step 4 Router# show running-config interface Verifies the change to the port. End with CNTL/Z. one per line. The VTP enable value will be applied only when a port becomes switched port in trunk mode. 1. gigabitethernet.2SX OL-13013-06 22-17 . type = fastethernet. one per line. perform this task: Command Purpose 1 Step 1 Router(config)# interface type slot/port Selects an interface to configure.2(33)SXH and later releases. type slot/port Step 5 Router# show vtp interface Verifies the configuration. To configure VTP mode. not forwarded. you can also configure VTP mode on a per-trunk basis. Step 2 Router(config-if)# vtp Enables VTP on the specified port.. End with CNTL/Z. in VTP version 3..2(33)SXI and later releases. Cisco IOS Software Configuration Guide. Router(config)# interface gigabitethernet 3/5 Router(config-if)# no vtp Router(config-if)# end Router# This example shows how to verify the configuration change: Router# show vtp interface gigabitethernet 3/5 Interface VTP Status ------------------------------------ GigabitEthernet3/5 disabled Router# This example shows how to verify the interface: Router# show vtp interface Interface VTP Status ------------------------------------ GigabitEthernet3/1 enabled GigabitEthernet3/2 enabled GigabitEthernet3/3 enabled GigabitEthernet3/4 enabled GigabitEthernet3/5 disabled GigabitEthernet3/6 enabled . Release 12. Chapter 22 Configuring VTP Configuring VTP Configuring VTP Mode on a Per-Port Basis With Release 12. Router(config)# interface gigabitethernet 3/5 Router(config-if)# vtp Router(config-if)# end Router# This example shows how to disable VTP mode on a port: Router# config terminal Enter configuration commands.

see the documents listed on this page: http://www.cisco.--------------------------- Fa5/8 43071 42766 5 Tip For additional information about Cisco Catalyst 6500 Series Switches (including configuration examples and troubleshooting information). perform this task: Command Purpose Router# show vtp counters Displays VTP statistics.---------------. This example shows how to display VTP statistics: Router# show vtp counters VTP statistics: Summary advertisements received : 7 Subset advertisements received : 5 Request advertisements received : 0 Summary advertisements transmitted : 997 Subset advertisements transmitted : 13 Request advertisements transmitted : 3 Number of config revision errors : 0 Number of config digest errors : 0 Number of V1 summary errors : 0 VTP pruning statistics: Trunk Join Transmitted Join Received Summary advts received from non-pruning-capable device ---------------.html Participate in the Technical Documentation Ideas forum Cisco IOS Software Configuration Guide.com/en/US/products/hw/switches/ps708/tsd_products_support_series_home. Chapter 22 Configuring VTP Configuring VTP Displaying VTP Statistics To display VTP statistics. Release 12.2SX 22-18 OL-13013-06 .---------------. including VTP advertisements sent and received and VTP errors.