CoreOS, Ansible, OpenStack, and a Private Registry

This took me longer than I want to admit to figure out, so I thought I'd post this solution here.  I'm doing this on Cisco's OpenStack Private Cloud (COPC) (formerly known as Metacloud). Problem:  Want to deploy a CoreOS instance that can access docker images from a private registry.  I want to do this with Ansible. Why its hard:  Not a lot of good documentation on this put in one place.  I kept getting this error:

FATA[0004] Error: v1 ping attempt failed with error: Get https://10.2.3.7:5000/v1/_ping: EOF. If this private registry supports only HTTP or HTTPS with an unknown CA certificate, please add `--insecure-registry 10.2.3.7:5000` to the daemon's arguments. In the case of HTTPS, if you have access to the registry's CA certificate, no need for the flag; simply place the CA certificate at /etc/docker/certs.d/10.2.3.7:5000/ca.crt 

Really started to aggravate me.

Ansible Playbook

Here's the playbook in its final glory:

- name: Ensure Test image is up. 
  connection: local
  hosts: local
  vars_files:
   - vars/metacloud_vars.yml

  tasks: 
  - name: Ensure Test Image is up. 
    nova_compute:
      state: present
      auth_url: "{{ lookup('env', 'OS_AUTH_URL') }}"
      login_username: "{{ lookup('env', 'OS_USERNAME') }}"
      login_password: "{{ lookup('env', 'OS_PASSWORD') }}"
      login_tenant_name: "{{ lookup('env', 'OS_TENANT_NAME') }}"
      name: coreostest
      image_name: "{{ coreos_image_name }}"
      key_name: "{{ keypair }}"
      flavor_id: "{{ m1large }}"
      meta: 
        group: web-servers
      security_groups: "{{ security_group }}"
      user_data:  "{{ lookup('file', 'files/coreos-cloud-config.yaml') }}"

The coreos-cloud-config.yaml file looks like this:

#cloud-config

coreos:
  units:
    - name: docker.service
      drop-ins: 
        - name: 50-insecure-registry.conf
          content: |
            [Service]
            Environment='DOCKER_OPTS=--insecure-registry=ci:5000 '

There were a few things to note:

1. If I used the config_drive: yes like it said on some documentation somewhere with this then I had some problems.
2. I was using a different configuration for the cloud-config that had me do files instead.  Not sure why I did this, but figured it out by using the other flag.  As you can see I even opened up a problem on CoreOS github repo.   I think this is what you need to do in order to solve your own problems.  And the reason we all need a rubber duck.
3. The CoreOS documentation shows a IP address range, but I just put in the actual registry for this and it works great.

Hoping that helps someone else not struggle like I did for hours...