Comment 2 for bug 1633450

Users hitting this issue will see something like this:

[2016-10-18 06:55:44,771] (os-refresh-config) [INFO] Completed phase post-configure
os-refresh-config completed successfully
Not creating flavor "baremetal" because it already exists.
Not creating flavor "control" because it already exists.
Not creating flavor "compute" because it already exists.
Not creating flavor "ceph-storage" because it already exists.
Not creating flavor "block-storage" because it already exists.
Not creating flavor "swift-storage" because it already exists.
Not creating default plan "overcloud" because it already exists.
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/lib/python2.7/site-packages/instack_undercloud/undercloud.py", line 1195, in install
    _post_config(instack_env)
  File "/usr/lib/python2.7/site-packages/instack_undercloud/undercloud.py", line 1177, in _post_config
    _post_config_mistral(mistral)
  File "/usr/lib/python2.7/site-packages/instack_undercloud/undercloud.py", line 1147, in _post_config_mistral
    "undercloud_ceilometer_snmpd_password": snmpd_password
  File "/usr/lib/python2.7/site-packages/mistralclient/api/v2/environments.py", line 56, in create
    return self._create('/environments', kwargs)
  File "/usr/lib/python2.7/site-packages/mistralclient/api/base.py", line 92, in _create
    self._raise_api_exception(resp)
  File "/usr/lib/python2.7/site-packages/mistralclient/api/base.py", line 140, in _raise_api_exception
    error_message=error_data)
mistralclient.api.base.APIException: Duplicate entry for Environment: ['name']
Command 'instack-install-undercloud' returned non-zero exit status 1