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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

page 22-3 • Understanding VTP Advertisements. Note For complete information on configuring VLANs. Cisco IOS Software Configuration Guide. page 22-4 • Understanding VTP Version 2. there is a VTP-primary server and a VTP-secondary server. VTP version 3 is supported. VLANs in the range 1006 to 4094 are removed from VTP control. Chapter 22 Configuring VTP Understanding VTP to use VTP in your network. 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. In VTP version 3. Release 12. • The pruning of VLANs still applies to VLANs 1 to 1000 only. A secondary server can only back up the updated VTP configuration received from the primary server in the NVRAMs. If you configure the switch as VTP transparent. With VTP.2(33)SXI and later releases. • In Cisco IOS Release 12. If converting from VTP version 3 to VTP version 2. “Configuring VLANs. 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. page 22-3 • Understanding VTP Authentication. A network device can be configured to be in one and only one VTP domain. If the switch receives a VTP advertisement over a trunk link. By default. In Cisco IOS releases prior to Release 12. The switch ignores advertisements with a different management domain name or an earlier configuration revision number. it inherits the management domain name and the VTP configuration revision number.” These sections describe how VTP works: • Understanding the VTP Domain. • Extended-range VLANs are supported only in VTP version 3. The status of the primary and secondary servers is a runtime status and is not configurable. when using VTP version 1 and version 2.2(33)SXI and later releases. You can enter the vtp primary privileged EXEC mode command to specify a primary server. you can create and modify VLANs but the changes affect only the individual switch. 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. all devices come up as secondary servers.2(33)SXI. see Chapter 23. page 22-2 • Understanding VTP Modes. page 22-4 • Understanding VTP Version 3. In VTP version 3. a VTP server is used to back up the database to the NVRAM and allows you to change the database information. You make global VLAN configuration changes for the domain using either the command-line interface (CLI) or Simple Network Management Protocol (SNMP). The valid VLAN ranges are as follows: • VTP version 1 and version 2 support VLANs 1 to 1000 only. the entire VLAN range is supported (VLANs 1 to 4094). 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.2SX 22-2 OL-13013-06 . VTP version 3 is supported. page 22-5 • Understanding VTP Pruning. In Cisco IOS Release 12.

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

you can configure the authentication password to be hidden using the vtp password command.2(33)SXI. 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]). 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. Chapter 22 Configuring VTP Understanding VTP • A start index. The password-string argument is an ASCII string from 1 to 64 characters identifying the administrative domain for the device. Understanding VTP Version 2 If you use VTP in your network. Because only one domain is supported. the secret that is used to validate the received VTP updates is visible in plain text in the show commands and the NVRAM file.2SX 22-4 OL-13013-06 .dat. In the event that a device in a VTP domain is compromised. • Version-Dependent Transparent Mode—In VTP version 1. you must decide whether to use VTP version 1 or version 2. In VTP version 3. you must use version 2. Note If you are using VTP in a Token Ring environment. it does not appear in plain text in the configuration. the secret associated with the password is saved in hexadecimal format in the running configuration. • VTP version 3 adds the following fields to the subset advertisement request: – A primary server ID. For more information about Token Ring VLANs. • 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. Cisco IOS Software Configuration Guide. – An instance number. Release 12. 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. When you configure the authentication password to be hidden. see the “Understanding VLANs” section on page 23-1. – On all trunks when the database of a switch becomes invalid as a result of a configuration change or a takeover message. In Cisco IOS Release 12. Instead. Understanding VTP Authentication In releases prior to Cisco IOS Release 12. even for TLVs that it is not able to parse. – A window size. VTP version 3 is supported. – On a specific trunk where a superior database has been advertised. The unrecognized TLV is saved in NVRAM.2(33)SXI and later releases. const_nvram:vlan. – A start index. the administrator had to change the VTP secret across all the devices in the VTP domain.

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

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

when any given VLAN exists or not. VTP pruning takes effect several seconds after you enable it. 5. VTP pruning does not prune traffic from pruning-ineligible VLANs.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. Cisco IOS Software Configuration Guide. By default. VLAN 1 is always pruning ineligible. VLANs 2 through 1000 are pruning eligible. use the switchport trunk pruning vlan command (see the “Configuring a Layer 2 Switching Port as a Trunk” section on page 17-10). traffic from VLAN 1 cannot be pruned. and when the LAN port is currently trunking or not. VTP pruning operates when a LAN port is trunking. You can set VLAN pruning eligibility when VTP pruning is enabled or disabled for the VTP domain. To configure VTP pruning on a trunking LAN port. Release 12. 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). 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. Figure 22-2 Flooding Traffic with VTP Pruning Switch 4 Interface 2 Interface 4 Flooded traffic is pruned. The broadcast traffic from Switch 1 is not forwarded to Switches 3.2SX OL-13013-06 22-7 .

Even when a VTP version 3 device detects a VTP version 2 device on a trunk port. MST database mode Transparent Cisco IOS Software Configuration Guide. it will be configured as a VTP version 2 device if VTP version 2 conflicts do not exist. page 22-8 • Interaction Between VTP Version 3 and VTP Version 1 Devices.2SX 22-8 OL-13013-06 . 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. VTP Default Configuration Table 22-1 shows the default VTP configuration. to allow two kinds of neighbors to coexist on the trunk. If the VTP version 3 device does not receive VTP version 2 packets for an interval of time on the trunk port. version 3 does not configure all the VTP version 3-capable devices in the domain to start behaving as VTP version 3 systems. the VTP version 3 device stops transmitting VTP version 2 packets on that trunk port. the VTP version 3 device sends a scaled-down version of the VLAN database on that particular trunk in a VTP version 2 format. A VTP version 3 device does not accept configuration from a VTP version 2 (or VTP version 1) device. 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. VTP version 3 sends VTP version 3 and VTP version 2 updates on VTP version 2-detected trunks. Unlike in VTP version 2. 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. 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. 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. the VTP version 1 or 2 VLAN database mode is carried over to VTP version 3 VLAN database mode. VTP version 1-only capable devices cannot interoperate with VTP version 3 devices. the VTP version 3 device continues to send VTP version 3 packets in addition to VTP version 3 device 2 packets. Release 12. For example.

Caution If you configure VTP in secure mode. not on all network devices in the VTP domain.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. You cannot configure pruning eligibility separately for each trunk. • The pruning-eligibility configuration applies globally to all trunks on the switch. enter the no vtp file command to return to the default configuration. • VTP version 3 supports propagation of any database in a domain by allowing you to configure a primary and secondary server. follow these guidelines and restrictions: • Supervisor engine redundancy does not support nondefault VLAN data filenames or locations. Cisco IOS Software Configuration Guide. • All network devices in a VTP domain must run the same VTP version. If you convert from VTP version 3 to VTP version 2. • Before installing a redundant supervisor engine. • In a Token Ring environment. all of the version 2-capable network devices in the domain enable VTP version 2. Release 12. the VLANs in the range 1006 to 4094 are removed from VTP control. • VTP version 1 and VTP version 2 do not propagate configuration information for extended-range VLANs (VLAN numbers 1006 to 4094). VTP pruning for the entire management domain is enabled or disabled. • VTP version 3 supports extended-range VLANs (VLAN numbers 1006 to 4094). pruning eligibility for those VLANs is affected on that switch only. • 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). • When you configure VLANs as pruning eligible or pruning ineligible. • When you enable or disable VTP pruning on a VTP server. You must configure extended-range VLANs manually on each network device. 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.2SX OL-13013-06 22-9 . • 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. you must enable VTP version 2 for Token Ring VLAN switching to function properly. When you enable VTP version 2 on a network device. • You must configure a password on each network device in the management domain when in secure mode.

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

Router(config)# no vtp password Clears the password. perform this task: Command Purpose Router(config)# vtp password password-string [hidden Configures a password. Note When entering the secret keyword. Configuring VTP Version 3 Password To configure the VTP version 3 password.2SX OL-13013-06 22-11 . 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. 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. Router# This example shows how to configure a VTP password in EXEC mode: Router# vtp password WATER Setting device VLAN database password to WATER. the password is not stored in the running-config file. Router# Note If you configure a VTP password in EXEC mode. Router# Note The password is not stored in the running-config file. Release 12. 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. the password-string must be entered in 32-digit hexadecimal format. which can be from 1 to 64 characters | secret] long or in 32-digit hexadecimal format.

• Any domain configuration change (version. 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. • Switchover between redundant supervisors. 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. Chapter 22 Configuring VTP Configuring VTP Configuring VTP Version 3 Server Type To specify a primary server.-------------------- VLANDB Yes 00d0.2SX 22-12 OL-13013-06 . • Takeover from another server.-------------. one of the following conditions must be met: • System reload. domain password).---.00b8.00b8. perform this task: Command Purpose Step 1 Router# vtp primary [vlan | mst] [force] Configure this device as the primary server.1400 1 stp7 Do you want to continue (y/n) [n]? y Router# Cisco IOS Software Configuration Guide. domain name. Release 12. 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 -----------. The vtp primary command does not have a no form. • Change in the mode configuration.-------. 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. Step 2 Router# show vtp status Verifies the configuration. To return to the secondary server status.1400=00d0.-------------.

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

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. Caution In VTP version 3. Router(config)# no vtp version Reverts to the default (VTP version 1). Note Prior to configuring VTP version 3. both the primary and secondary servers may exist on an instance in the domain. 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.0040 Feature VLAN: -------------- Cisco IOS Software Configuration Guide. In Cisco IOS Release 12. To enable VTP version 3.c724. the network administrator has to manually configure VTP version 3 on the switches that need to run VTP version 3. Release 12. Router(config)# This example shows how to enable VTP version 2 with any release: Router# vtp version 2 V2 mode enabled. You can enable version 3 in global configuration mode only. you must ensure that the spanning-tree extend system-id command has been enabled. 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. perform this task: Command Purpose Step 1 Router(config)# vtp version 3 Enables VTP version 3.2SX 22-14 OL-13013-06 .2(33)SXI and later releases.

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. perform this task: Command Purpose Step 1 Router(config)# vtp mode {client | server | Configures the VTP mode. Note You cannot clear the domain name.2SX OL-13013-06 22-15 . 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. the switch learns the domain name from the VTP server in the domain. Step 4 Router# show vtp status Verifies the configuration. which can be up to 32 characters long. Release 12. Note When VTP is disabled. transparent | off} {vlan | mst | unknown} Step 2 Router(config)# vtp domain domain-name (Optional for server mode) Defines the VTP domain name.0000. 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. VTP server mode requires a domain name. Step 3 Router(config)# end Exits VLAN configuration mode. 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. If the switch has a trunk connection to a VTP domain.

c724. Chapter 22 Configuring VTP Configuring VTP Setting device to VTP CLIENT mode.2SX 22-16 OL-13013-06 .0040 Feature VLAN: -------------- VTP Operating Mode : Server Number of existing VLANs : 6 Number of existing extended VLANs : 0 Configuration Revision : 0 Primary ID : 0000. Router(config)# vtp mode off Setting device to VTP OFF mode. 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 : 0015.0000 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. 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. 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. End with CNTL/Z.0000. Release 12.

gigabitethernet. Cisco IOS Software Configuration Guide. The VTP enable value will be applied only when a port becomes switched port in trunk mode. Step 3 Router(config-if)# end Exits interface configuration mode. type slot/port Step 5 Router# show vtp interface Verifies the configuration. 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. Chapter 22 Configuring VTP Configuring VTP Configuring VTP Mode on a Per-Port Basis With Release 12. End with CNTL/Z. Step 4 Router# show running-config interface Verifies the change to the port.2(33)SXI and later releases. type = fastethernet. or tengigabitethernet This example shows how to configure VTP mode on a port: Router# config terminal Enter configuration commands. one per line. perform this task: Command Purpose 1 Step 1 Router(config)# interface type slot/port Selects an interface to configure. Step 2 Router(config-if)# vtp Enables VTP on the specified port. in VTP version 3. Release 12. Incoming and outgoing vtp pdus are blocked. not forwarded. End with CNTL/Z.. you can configure VTP mode on a per-port basis. To configure VTP mode. one per line. 1. you can also configure VTP mode on a per-trunk basis.2(33)SXH and later releases. 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 .2SX OL-13013-06 22-17 .

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 ---------------.--------------------------- Fa5/8 43071 42766 5 Tip For additional information about Cisco Catalyst 6500 Series Switches (including configuration examples and troubleshooting information). including VTP advertisements sent and received and VTP errors.---------------.---------------. Release 12. Chapter 22 Configuring VTP Configuring VTP Displaying VTP Statistics To display VTP statistics. see the documents listed on this page: http://www. perform this task: Command Purpose Router# show vtp counters Displays VTP statistics.cisco.html Participate in the Technical Documentation Ideas forum Cisco IOS Software Configuration Guide.2SX 22-18 OL-13013-06 .com/en/US/products/hw/switches/ps708/tsd_products_support_series_home.