VLAN Trunking Protocol -- VTP
bekijk de theorie: ccna-3v6_scaling-vlans
referentie: filezilla part 11 - ethernet vlans-switching p136(215)-p162(241)
LAB vtplabs
sjabloon: vlan_sjabloon
wikipedia: https://en.wikipedia.org/wiki/VLAN_Trunking_Protocol
Upside: VTP provides the following benefits:
VLAN configuration consistency across the layer 2 network
Dynamic distribution of added VLANs across the network
Plug-and-play configuration when adding new VLANs
Downside: "VTP BOMB"
When a new switch is added to the network, by default it is configured with no VTP domain name or password, but in VTP server mode. If no VTP Domain Name has been configured, it assumes the one from the first VTP packet it receives. Since a new switch has a VTP configuration revision of 0, it will accept any revision number as newer and overwrite its VLAN information if the VTP passwords match. However, if you were to accidentally connect a switch to the network with the correct VTP domain name and password but a higher VTP revision number than what the network currently has (such as a switch that had been removed from the network for maintenance and returned with its VLAN information deleted) then the entire VTP Domain would adopt the VLAN configuration of the new switch which is likely to cause loss of VLAN information on all switches in the VTP Domain, leading to failures on the network. Since Cisco switches maintain VTP configuration information separately from the normal configuration, and since this particular issue occurs so frequently, it has become known colloquially as the "VTP Bomb".
Before creating VLANs on the switch that will propagate via VTP, a VTP domain must first be set up. A VTP domain for a network is a set of all contiguously trunked switches with the matching VTP settings (domain name, password and VTP version). All switches in the same VTP domain share their VLAN information with each other, and a switch can participate in only one VTP management domain. Switches in different domains do not share VTP information. Non-matching VTP settings might result in issues in negotiating VLAN trunks, port-channels or Virtual Port Channels.