The Lazy Networker

VTP (VLAN Trunking Protocol) has evolved over time, with VTP version 3 introducing significant improvements over VTP version 2. Below is a comparison of both versions.

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1. Key Differences Between VTP v2 and VTP v3

Feature	VTP v2	VTP v3
VLAN Range Support	Supports VLANs 1-1005	Supports VLANs 1-4094 (full range)
Private VLANs	Not supported	✅ Supports private VLANs
VTP Modes	Server, Client, Transparent	Server, Client, Transparent, Off
Server Authorization	Any VTP server can modify VLANs	✅ Only a primary server can modify VLANs
Extended VLAN Support (1006-4094)	❌ No	✅ Yes
VTP Pruning	Yes	✅ Improved pruning efficiency
Security	No authentication improvements	✅ Supports hidden passwords for security
MD5 Hashing for Authentication	Yes	✅ Yes (Improved)
Multiple Spanning Tree (MST) Support	No	✅ Yes

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2. When to Use VTP v3?

VTP v3 is ideal when:
✅ You need extended VLANs (1006-4094) support.
✅ You want to improve security and prevent accidental VLAN changes.
✅ You are using Private VLANs in your network.
✅ You need better MST (Multiple Spanning Tree) support.
✅ You want more control over which switches can modify VLANs (Primary Server Feature).

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3. How to Upgrade from VTP v2 to VTP v3

Before upgrading, ensure:
✅ All switches support VTP v3 (older switches may not).
✅ The switch is running VTP Server Mode.
✅ The VTP domain name is configured correctly.

Step-by-Step Upgrade to VTP v3

Enable VTP v3 on the Server Switch

configure terminal

vtp version 3

exit

Set a Primary VTP Server

vtp primary

This switch now has exclusive rights to make VLAN changes.

Verify the Upgrade

show vtp status

Ensure Clients Are Syncing

show vlan brief

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4. Summary: Should You Upgrade to VTP v3?

✅ YES, if:

• You need VLANs 1006-4094.
• You use Private VLANs.
• You want stronger security and better control over VLAN changes.

❌ NO, if:

• Your network has older switches that do not support VTP v3.
• You prefer manual VLAN configuration using VTP Transparent Mode.