VTP Modes and Versions: VTP v1, VTP v2 and VTP v3

In this article, we will discuss the four VTP modes namely client mode, server mode, transparent mode, off mode and three versions, VTP v1, VTP v2 and VTP v3, their differentiation and parameters.

VTP is a Cisco proprietary protocol that propagates the information of Virtual Local Area Networks (VLAN) on the whole local area network. VTP protocol carries VLAN information to all the switches in a VTP domain. VLAN Trunk Protocol (VTP) reduces administration in a Layer 2 network.

When you configure a new VLAN on one VTP server, the VLAN is distributed through all switches in the domain. This reduces the need to configure the same VLAN everywhere. VTP protocol is a Cisco-proprietary protocol that is available on most of the Cisco Catalyst series products.

VTP Modes

VTP operates in different modes, each with a specific purpose. While VTP version 1 and 2 support 3 modes of operation i.e. Server/Client/ Transparent, VTPs latest version 3 has introduced a new mode “Off“.

Server Mode

This is the default mode .It can create, modify and delete VLANs. The changes are advertised to other switches in the same VTP domain. It stores VLAN info in NVRAM (i.e., VLAN database is persistent after a reboot). You need at least one switch in server mode for VTP to work.

Client Mode

Client mode cannot create, modify, or delete VLANs. It receives updates from VTP servers and applies them. It does not store VLAN info in NVRAM (rebooting will lose VLAN info unless received again). It is useful for keeping VLANs consistent across the network.

Transparent Mode

transparent mode does not participate in VTP advertisements. It forwards VTP messages to other switches. It can create, modify, and delete VLANs, but changes are local only. VLAN info is stored in NVRAM, but not shared.

Off Mode

Off Mode is basically VTP Version 3 only. It disables VTP completely hence no VLAN updates are sent or received. The VLAN configuration is local only.

VTP Versions

While VTP has evolved over time, its key for us to understand how and what are the differentiating parameters of various versions of VTP – (VTP v1 , VTP v2 and VTP v3)

Download the comparison table: VTP v1 vs VTP v2 vs VTP v3

VTP v3 Enhancements

• Extended VLANs: Can now manage VLANs 1006–4094.
• Private VLANs: Supports configuration sharing for PVLANs.
• MST support: Can propagate MST region information.
• Primary Server Role: Only the primary server can make VLAN changes, reducing config errors.
• Improved security: Optionally enforces secure updates and stronger authentication.
• Persistent configuration: VLAN data is saved in the switch config, not just a separate database.

VTPv3 is highly recommended if you are deploying in larger or more complex environments that use extended VLANs, MST and Private VLANs.

Continue Reading

VTP Version 3 Guide

How to Reset Revision Number in VTP?

Are you preparing for your next interview?

If you want to learn more about VTP, then check our e-book on VTP Interview Questions and Answers in easy to understand PDF Format explained with relevant Diagrams (where required) for better ease of understanding.

ABOUT THE AUTHOR

Rashmi Bhardwaj

Founder of AAR TECHNOSOLUTIONS, Rashmi is an evangelist for IT and technology. With more than 12 years in the IT ecosystem, she has been supporting multi domain functions across IT & consultancy services, in addition to Technical content making.

You can learn more about her on her linkedin profile – Rashmi Bhardwaj