I have set up a local registry using the following method as per official doc. 

docker run -d \
 --network host \
 --name registry \
 --restart=always \
 -e REGISTRY_HTTP_ADDR=0.0.0.0:4000 \
 -v registry:/var/lib/registry \
 registry:2

After that I ran the following command to import all images to the local registry. 

docker images | grep kolla | grep -v local | awk '{print $1,$2}' | while read -r image tag; do
    new_image_name=${image#"quay.io/"}
    docker tag ${image}:${tag} "localhost:4000"/${new_image_name}:${tag}
    docker push localhost:4000/${new_image_name}:${tag}
done

Now i can see images in local registry using docker images command

(venv-kolla) root@kolla-infra-1:/etc/kolla# docker images | grep localhost
localhost:4000/openstack.kolla/ubuntu-source-nova-novncproxy                   yoga      01dc100dc65a   2 days ago     1.2GB
localhost:4000/openstack.kolla/ubuntu-source-horizon                           yoga      a016e1f5b9af   2 days ago     1.1GB
localhost:4000/openstack.kolla/ubuntu-source-nova-conductor                    yoga      381a64a368bd   2 days ago     1.11GB
localhost:4000/openstack.kolla/ubuntu-source-nova-api                          yoga      f90a15a09142   2 days ago     1.11GB

....

....

I have added it in global.yml 

docker_registry: 10.73.0.181:4000
docker_registry_insecure: yes

Now when i am trying to add compute nodes then I get a registry error like the following. Not sure why its trying to use https://10.73.0.181:4000/v2 instead of http;// 

TASK [common : include_tasks] ****************************************************************************************************************************************************
included: /root/venv-kolla/share/kolla-ansible/ansible/roles/common/tasks/pull.yml for kolla-comp-2

TASK [service-images-pull : common | Pull images] ********************************************************************************************************************************
FAILED - RETRYING: common | Pull images (3 retries left).
FAILED - RETRYING: common | Pull images (2 retries left).
FAILED - RETRYING: common | Pull images (1 retries left).
failed: [kolla-comp-2] (item=fluentd) => {"ansible_loop_var": "item", "attempts": 3, "changed": true, "item": {"key": "fluentd", "value": {"container_name": "fluentd", "dimensions": {}, "enabled": true, "environment": {"KOLLA_CONFIG_STRATEGY": "COPY_ALWAYS"}, "group": "fluentd", "image": "10.73.0.181:4000/openstack.kolla/ubuntu-source-fluentd:yoga", "volumes": ["/etc/kolla/fluentd/:/var/lib/kolla/config_files/:ro", "/etc/localtime:/etc/localtime:ro", "/etc/timezone:/etc/timezone:ro", "kolla_logs:/var/log/kolla/", "fluentd_data:/var/lib/fluentd/data/"]}}, "msg": "'Traceback (most recent call last):\\n  File \"/usr/lib/python3/dist-packages/docker/api/client.py\", line 261, in _raise_for_status\\n    response.raise_for_status()\\n  File \"/usr/lib/python3/dist-packages/requests/models.py\", line 940, in raise_for_status\\n    raise HTTPError(http_error_msg, response=self)\\nrequests.exceptions.HTTPError: 500 Server Error: Internal Server Error for url: http+docker://localhost/v1.41/images/create?tag=yoga&fromImage=10.73.0.181%3A4000%2Fopenstack.kolla%2Fubuntu-source-fluentd\\n\\nDuring handling of the above exception, another exception occurred:\\n\\nTraceback (most recent call last):\\n  File \"/tmp/ansible_kolla_docker_payload_6o9nw9xd/ansible_kolla_docker_payload.zip/ansible/modules/kolla_docker.py\", line 381, in main\\n  File \"/tmp/ansible_kolla_docker_payload_6o9nw9xd/ansible_kolla_docker_payload.zip/ansible/module_utils/kolla_docker_worker.py\", line 450, in pull_image\\n    json.loads(line.strip().decode(\\'utf-8\\')) for line in self.dc.pull(\\n  File \"/usr/lib/python3/dist-packages/docker/api/image.py\", line 415, in pull\\n    self._raise_for_status(response)\\n  File \"/usr/lib/python3/dist-packages/docker/api/client.py\", line 263, in _raise_for_status\\n    raise create_api_error_from_http_exception(e)\\n  File \"/usr/lib/python3/dist-packages/docker/errors.py\", line 31, in create_api_error_from_http_exception\\n    raise cls(e, response=response, explanation=explanation)\\ndocker.errors.APIError: 500 Server Error: Internal Server Error (\"Get \"https://10.73.0.181:4000/v2/\": http: server gave HTTP response to HTTPS client\")\\n'"}
FAILED - RETRYING: common | Pull images (3 retries left).