unable to delete stack because IP is still being used

[Removed by request]

creating a stack with (partial paste)
  server:
    type: OS::Nova::Server
    properties:
      availability_zone: { get_param: availability_zone }
      flavor: { get_param: flavor }
      image: { get_param: image }
      key_name: { get_param: key_name }
      networks:
        - uuid: { get_param: private_network_id }

and
  public_network:
    type: OS::Neutron::Net
    properties:
      name: {get_param: public_net_name}
      shared: {get_param: public_net_external}
      value_specs: {
        "router:external":"true",
        "provider:network_type":"vxlan"}

  public_subnet:
    type: OS::Neutron::Subnet
    properties:
      name: {get_param: public_subnet_name}
      network_id: {get_resource: public_network}
      ip_version: 4
      cidr: {get_param: public_net_cidr}
      gateway_ip: {get_param: public_net_gateway}

  private_network:
    type: OS::Neutron::Net
    properties:
      name: {get_param: private_net_name}
      shared: {get_param: private_net_external}

  private_subnet:
    type: OS::Neutron::Subnet
    properties:
      name: {get_param: private_subnet_name}
      network_id: {get_resource: private_network}
      ip_version: 4
      cidr: {get_param: private_net_cidr}
      gateway_ip: {get_param: private_net_gateway}

  router:
    type: OS::Neutron::Router
    properties:
      admin_state_up: {get_param: router_up}
      external_gateway_info:
        network: {get_resource: public_network}

  router_gateway:
    type: OS::Neutron::RouterGateway
    properties:
      router_id: {get_resource: router}
      network_id: {get_resource: public_network}

  router_interface:
    type: OS::Neutron::RouterInterface
    properties:
      router_id: {get_resource: router}
      subnet_id: {get_resource: private_subnet}

Nova returned 500, the server is not created, but the neutron port was. From this point, delete fails until you manually remove the 'used' ports.
Its a nova issue, but perhaps heat can do something to clear the resources.

[Steve Baker (steve-stevebaker)]

If heat created the port it will be possible for heat to delete it, however if nova created the port then heat can't do anything.

Depending on the code path taken in the server resource, either could be the case.