VLAN Trunking Protocol (VTP)

VTPv1/2

• Synchronizes VLANs between switches automatically
• Not a requirement
• Does not define broadcast domain
• Consists of VTP Server, Client, and Transparent mode

VTP Server
– Creates VLANs
– Advertises VLANs
– Installs VLANs from other advertisements – similar to client.

VTP Client
– Cannot create VLANs
– Can advertise VLANs
– Installs VLANs from other advertisements

VTP Transparent
– Creates locally significant VLANs
– Forwards VTP advertisements but does not listen or install VLANs from advertisements

Configuration Revision
– Sequence number for DB
– Highest Number wins
– VTP works towards having same DB number on all switches in VTP domain.

VTP Pruning
– Only in server and client mode
– Reduces necessary traffic over VTP peers

Configuration:

• Domain – router(config)#vtp domain mickx009.org
  • Default configuration this will pass if trunk between two switches.
• Password – router(config)#vtp password CISCO
  • Does not pass between VTP domain members.
  • VTP updates will not pass if same password is not entered on both sides.
• Changing Mode – router(config)#vtp mode <server,client,transparent,off>

VTPv3 Enhancements:

• Security
  • Primary Server – only device allowed to add to advertisements
• Advertisements
  • MST
  • PVLANs
  • Extended VLANs
• Disabling
  • Globally
  • Per link

Configuration:

• Enabling VTPv3
  • router(config)#vtp domain mickx009.org – before enabling v3
  • router#vtp primary <vlan,mst> – On device you want as primary – only device allowed to update database.