Simple VTP Question

websponge

Hi, just a quick question,

The whole point of VTP in a large organisation is to propagate vlan database, which I can see the value of, but im curious, if you had 100 switches on 100 different floors, and you added a new vlan to the server switch, you still need to goto every switch that needs access to this vlan to configure the correct port and up the port?

doesnt this seem pointless? you have to goto each switch anyway so you could just configure the vlan at the same time and do away with VTP..?

EdTheLad

Normally when switches are installed the installation technical will put a base config on the switch, this config would include setting trunk ports, access ports, spanning-tree, management ip addresses,vtp etc.. with vtp running in client mode for instance, the switch will be able to learn vlans on the network. Imagine a new vlan is configured 2 weeks after installation, this will be learned dynamically, you are assuming the switch configuration will stay static after installation which is not the case.

networker050184

You still have to assign the access ports, but imagine there are 5 switches in between the two access switches that will be using this VLAN. Without VTP you would still need to log into every transit switch (and any switch that may be used as an alternate path) and add the VLAN so traffic can pass.

websponge

gotcha! thanks both, trunks ports can learn dynamically the new vlan, so no need to configure transit switches as you said.

Cheers

fredrikjj

I've only briefly looked at VTP so far, but isn't the automatic "pruning" the big selling point, not administrating vlans per se?

networker050184

The main selling point is the automated provisioning. I haven't seen many people enable pruning even when they do use VTP.