Assign Floating IPs to VMs in a Heat Stack

Floating IPs can be assigned to VMs that are on private networks in order for them to be accessible from an external network.

This document assumes that Floating IPs have been assigned to your project. If you do not have any floating IPs in your project, please contact the cloud team at cloud-support@stfc.ac.uk

There are two similar methods for assigning a floating IP to a virtual machine in a heat stack.

1. Use the resource OS::Neutron::FloatingIPAssociation.

2. Add the ID of the floating IP in the networks property of the OS::Nova::Server Resource

For both methods, OS::Neutron::Port is used in order to define a port on the VM on which to attach the floating IP.

To get the ID of the floating IPs, use the command:

openstack floating ip list

This will return a list of floating IPs containing the IP address, pool, port, and ID.

Using OS::Neutron::FloatingIPAssociation

heat_template_version: <template-version>

parameters:
  <define parameters here>

resources:
  private_network_port: # define the VM port which will be used to attach the floating IP
    type: OS::Neutron::Port
    properties:
      network_id: <private network ID> #private network ID
      security_groups: [{get_param: security_group_id}]

  test_VM:
    type: OS::Nova::Server
    properties:
      image: {get_param: image_id}
      flavor: {get_param: flavor_id}
      key_name: {get_param: key_name}
      networks:
        - port: {get_resource: private_network_port}

  floating_ip_association:
    type: OS::Neutron::FloatingIPAssociation
    properties:
      floatingip_id: <ID of Floating IP address> #ID of IP address to assign to VM
      port_id: {get_resource: private_network_port} #port to attach floating IP

Using the Network Property in OS::Nova::Server

heat_template_version: <temlate-version>

parameters:
  <define parameters>

resources:
  private_network_port:
    type: OS::Neutron::Port
    properties:
      network_id: <private-network-id> #private network ID
      security_groups: [{get_param: security_group_id}]

  test_VM:
    type: OS::Nova::Server
    properties:
      image: {get_param: image_id}
      flavor: {get_param: flavor_id}
      key_name: {get_param: key_name}
      networks: [{network: <private-network-id>, port: {get_resource: private_network_port}, floating_ip: <floating-ip-id> }]