[Queens][neutron] multiple networks with same vlan id

Hello, I trying to create multiple networks with the same vlan id and different address but it is impossibile because neutron returns vlan id is already present. I tried with success on vcenter and it works. On openstack I can create more subnets with different adresses under the same vlan id, but instances receive static routes from dhcp for all subnets. Any workaround ? I am also trying with segments but they do not seem to fit my case. Regards Ignazio