Virtual LAN Trunking Protocol
• VTP is a CISCO proprietary protocol
• used to share the VLAN configurations with multiple switches and to maintain consistency throughout that network.
• Information will be passed only if switches connected with FastEthernet or higher ports.
• VTP allows an administrator to add, delete, and rename VLANs-information that is
then propagated to all other switches in the VTP domain.
• Note: Switches Should be configure with same Domain. Domain are not Case sensitive.
VTP Mode are of three types :
o A Switch configured in Server mode can Add , Modify and Delete VLAN’s
o A Default VTP mode for all switches
o A switch configured in Client mode cannot Add , Modify and Delete its VLAN configurations
o Doesn’t store its VLAN configuration information in the NVRAM. Instead learns it from the server every time it boots up
o Changes in one transparent switch will not affect any other switch.
• Preserves bandwidth by configuring it to reduce the amount of broadcasts, multicasts,
and unicast packets.
• VTP pruning only sends broadcasts to trunk links that truly must have the information.
• Enabling pruning on a VTP server, enables it for the entire domain.
• By default, VLANs 2 through 1005 are pruning-eligible, but VLAN 1 can never prune
because it’s an administrative VLAN.
Switch(config)# VTP Password <password>
Switch(config)# VTP Mode <server/client/transparent>
Switch(config)# VTP pruning
VLAN Trunking Protocol (VTP) is a Layer 2 messaging protocol that maintains VLAN
configuration consistency throughout a common administrative domain by managing VLANs’
additions, deletions, and name changes across multiple switches. Without VTP, you would
have to add VLAN information in all switches in your network.
A VTP domain is one or more interconnected switches that share the same VTP environment.
A switch can be in only one VTP domain, and all VLAN information is propagated to all
switches in the same VTP domain.
The three VTP modes are
VTP advertisements are flooded throughout the management domain every 5 minutes or
whenever a change occurs in VLAN configuration.
What is included in VTP advertisements?
VTP advertisements include the following:
VTP revision number
VLAN names and numbers
Information about switches that have ports assigned to each VLAN
What is one of the most important components of the VTP advertisement?
The revision number is one of the most important components of the VTP advertisement.
Every time a VTP server modifies its VLAN configuration, it increments the configuration number by 1.