VLAN Trunk Protocol (VTP)
121
allowed-vlans Display allowed vlans
joined-vlans Display joined vlans
joining-vlans Display joining vlans
prune-eligible Display pruning eligible vlans
<cr>
1900EN#sh trunk a allowed-vlans
1-4, 6-1004
1900EN#
VLAN Trunk Protocol (VTP)
V
LAN Trunk Protocol (VTP) was created by Cisco to manage all the
configured VLANs across a switched internetwork and to maintain consis-
tency throughout the network. VTP allows an administrator to add, delete,
and rename VLANs, and these changes would then be propagated to all
switches.
VTP provides the following benefits to a switched network:
Consistent configuration of VLANs across all switches in the network
Allowing VLANs to be trunked over mixed networks, like Ethernet to
ATM LANE or FDDI
Accurate tracking and monitoring of VLANs
Dynamic reporting when VLANs are added to all switches
Plug-and-play VLAN adding to the switched network
To allow VTP to manage your VLANs across the network, you must first
create a VTP server. All servers that need to share VLAN information must
use the same domain name, and a switch can be in only one domain at a time.
This means that a switch can share VTP domain information only with
switches configured in the same VTP domain.
A VTP domain can be used if you have more than one switch connected
in a network. If all switches in your network are in only one VLAN, then
VTP doesn't need to be used. VTP information is sent between switches via
a trunk port between the switches.
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