Unable to remove SoftwareDeployment resources during FFU

Issue

• During the Framework For Upgrades (FFU) process from Red Hat OpenStack Platform 13 to Red Hat OpenStack Platform 16.2. Heat is failing to remove SoftwareDeployment resources with the following error:

  resource_type: OS::Heat::SoftwareDeployment
  physical_resource_id: d05d933d-ea78-42da-a90e-9647a52137d8
  status: DELETE_FAILED
  status_reason: |
    ConnectFailure: resources.SshHostPubKeyDeployment: Unable to establish connecti
on to http://192.168.24.3:35357/v3/auth/tokens: HTTPConnectionPool(host='192.168.24
.3', port=35357): Max retries exceeded with url: /v3/auth/tokens (Caused by NewCo
nnectionError('<urllib3.connection.HTTPConnection object at 0x7f64557ae278>: Failed
 to establish a new connection: [Errno 111] ECONNREFUSED',))