A vlan backed segment is just using your existing physical network infrastructure on nsx-t. These vlan are just trunked on your network switch to your hosts and the transport zone for vlan configured. This is great for migrations as you can move your virtual machines from your old vCenter to a new vCenter utilizing nsx-t without having to change much.
Login to nsx-t manager
Click networking > click segments > click add segment
Give your segment a name
Select the transport zone using for vlan’s
Type in the VLAN id
Click save
Now change your virtual machine to the new segment, should be no outage if the virtual machine is on the same vlan
Done
Some backend useful information that I have configured also
My transport zone configuration
My host configuration
My edge configuration
dvs configurations for nsx-t
port group configuration for my edges
NSX-T version running
Ray