I'm bringing up a thread from June about DHCP relay with neutron networks in Ironic, specifically using unicast relay. The Triple-O docs do not have the plain config/neutron config to show how a regular Ironic setup would use DHCP relay. 

The Neutron segments docs state that I must have a unique physical network name. If my Ironic controller has a single provisioning network with a single physical network name, doesn't this prevent my use of multiple segments? 

Further, the segments docs state this: "The operator must ensure that every compute host that is supposed to participate in a router provider network has direct connectivity to one of its segments." (section 3 at https://docs.openstack.org/neutron/pike/admin/config-routed-networks.html#prerequisites - current docs state the same thing)
This defeats the purpose of using DHCP relay, though, where the Ironic controller does *not* have direct connectivity to the remote segment. 

Remote server: 10.146.30.32/27 VLAN 2116<-----> Router with DHCP relay <------> Ironic controller, provisioning network: 10.146.29.192/26 VLAN 2115

Thank you, 

Tom King