CHAPTER
15-1
Catalyst 2950 Desktop Switch Software Configuration Guide
78-14982-01
15

Configuring VTP

This c hapt er d escri b es how to us e t he V LAN Trunking Pr otoc ol ( VTP) a nd t he V LAN dat aba se for
managing V LANs .
Note For comple te syntax and us age inform ation for the co mmands used in this chapter, refer to th e command
refere nce fo r thi s r ele ase.
The ch apt er inc ludes th ese sect ions:
•Understa ndin g VT P, pag e 15- 1
•Configuring V TP, p age 15-6
•Monitoring VTP, page 15-16

Understandin g VTP

VTP is a Layer 2 messagin g protocol that maintains VLAN configuratio n consistency by managing the
addition, deletion, and renaming of VLANs on a network-wide basis. VTP minimizes misconf igurations
and co nfiguration inc onsistenc ies that ca n cause several problem s, such as dup licate VLA N names,
incorrect VLAN-type specifications, and security violations.
Before yo u create VLA Ns, you must decide whether to us e VTP in your net work. Using VT P, you can
make con figurati on ch an ge s cen tra lly on o ne or m ore swit che s and have those cha nges a uto ma tica lly
communicated to all the other switches in the network. W ithout VTP, you cannot send information about
VLANs to other switches. VTP configuration information is saved in the VTP VLAN database.
VTP only lea rn s abo ut no rm al-r a nge V LAN s (V LAN ID s 1 to 100 5). E xte nded- ra nge VLA Ns (VL AN
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 secti on contai ns informat ion about these VTP param eters:
•The VTP Do main, pa ge 15-2
•VTP Mode s, page 15-3
•VTP Ad vertis em ents , pag e 15-3
•VTP Version 2, page 15-4
•VTP Prun ing, page 15-4