[Observium] Groups based on VLANs

Hi, I want to track a patricidal VLAN and their ports on a bunch of switches, tough that the Group function in Observium could do that for me :) However I can't find any reference to VLAN, tried to use "ifVlan" but not sure that works, or I didn't do that part correctly.

The purpose is to track an internet facing vlan to easy see port graphs and to be able to create alerts from these.

//Anders