CHAPTER
14-1
Catalyst 2950 Desktop Switch Software Configuration Guide
78-11380-05
14
Configuring VTP
This chapter describes how to use the VLAN Trunking Protocol (VTP) and the VLAN database for
managing VLANs.
Note For complete syntax and usage information for the commands used in this chapter, refer to the command
reference for this release.
The chapter includes these sections:
• Understanding VTP, page 14-1
• Configuring VTP, page 14-6
• Monitoring VTP, page 14-16
Understanding VTP
VTP is a Layer 2 messaging protocol that maintains VLAN configuration consistency by managing the
addition, deletion, and renaming of VLANs on a network-wide basis. VTP minimizes misconfigurations
and configuration inconsistencies that can cause several problems, such as duplicate VLAN names,
incorrect VLAN-type specifications, and security violations.
Before you create VLANs, you must decide whether to use VTP in your network. Using VTP, you can
make configuration changes centrally on one or more switches and have those changes automatically
communicated to all the other switches in the network. Without VTP, you cannot send information about
VLANs to other switches. VTP configuration information is saved in the VTP VLAN database.
VTP only learns about normal-range VLANs (VLAN IDs 1 to 1005). Extended-range VLANs (VLAN
IDs greater than 1005) are not supported by VTP or stored in the VTP VLAN database. Extended-range
VLANs are only supported when the enhanced software image (EI) is installed.
This section contains information about these VTP parameters:
• The VTP Domain, page 14-2
• VTP Modes, page 14-3
• VTP Advertisements, page 14-3
• VTP Version 2, page 14-4
• VTP Pruning, page 14-4