Launching tmpnb on EC2 - ConnectionRefusedError in docker logs

[Winterflower]

Edit: I have it working with docker-compose and the .yml config, but would like to understand what happened with socket connection refused issue.

Hi Jupyter team! Complete Docker newbie here in action (trying to deploy an automated tmpnb environment for PyLadies) - so please be patient! I am trying to deploy tmbnb on a t2.micro EC2 instance running Ubuntu. I have run the following three commands from the tutorial

docker pull jupyter/minimal-notebook
export TOKEN=$( head -c 30 /dev/urandom | xxd -p )
docker run --net=host -d -e CONFIGPROXY_AUTH_TOKEN=$TOKEN --name=proxy jupyter/configurable-http-proxy --default-target http://127.0.0.1:9999
docker run --net=host -d -e CONFIGPROXY_AUTH_TOKEN=$TOKEN --name=tmpnb -v /var/run/docker.sock:/docker.sock jupyter/tmpnb python orchestrate.py --container-user=jovyan --command='jupyter notebook --no-browser --port {port} --ip=0.0.0.0 --NotebookApp.base_url=/{base_path} --NotebookApp.port_retries=0 --NotebookApp.token="" --NotebookApp.disable_check_xsrf=True'

However, the tmpnb docker logs are showing the following errors:

Traceback (most recent call last):
  File "orchestrate.py", line 504, in <module>
    main()
  File "orchestrate.py", line 426, in main
    assert_hostname=opts.assert_hostname,
  File "/srv/tmpnb/dockworker.py", line 68, in __init__
    **kwargs)
  File "/usr/local/lib/python3.4/site-packages/docker/client.py", line 77, in __init__
    self._version = self._retrieve_server_version()
  File "/usr/local/lib/python3.4/site-packages/docker/client.py", line 97, in _retrieve_server_version
    'Error while fetching server API version: {0}'.format(e)
docker.errors.DockerException: Error while fetching server API version: ('Connection aborted.', ConnectionRefusedError(111, 'Connection refused'))
Traceback (most recent call last):
  File "/usr/local/lib/python3.4/site-packages/requests/packages/urllib3/connectionpool.py", line 600, in urlopen
    chunked=chunked)
  File "/usr/local/lib/python3.4/site-packages/requests/packages/urllib3/connectionpool.py", line 356, in _make_request
    conn.request(method, url, **httplib_request_kw)
  File "/usr/local/lib/python3.4/http/client.py", line 1137, in request
    self._send_request(method, url, body, headers)
  File "/usr/local/lib/python3.4/http/client.py", line 1182, in _send_request
    self.endheaders(body)
  File "/usr/local/lib/python3.4/http/client.py", line 1133, in endheaders
    self._send_output(message_body)
  File "/usr/local/lib/python3.4/http/client.py", line 963, in _send_output
    self.send(msg)
  File "/usr/local/lib/python3.4/http/client.py", line 898, in send
    self.connect()
  File "/usr/local/lib/python3.4/site-packages/docker/unixconn/unixconn.py", line 41, in connect
    sock.connect(self.unix_socket)
ConnectionRefusedError: [Errno 111] Connection refused

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/lib/python3.4/site-packages/requests/adapters.py", line 423, in send
    timeout=timeout
  File "/usr/local/lib/python3.4/site-packages/requests/packages/urllib3/connectionpool.py", line 649, in urlopen
    _stacktrace=sys.exc_info()[2])
  File "/usr/local/lib/python3.4/site-packages/requests/packages/urllib3/util/retry.py", line 347, in increment
    raise six.reraise(type(error), error, _stacktrace)
  File "/usr/local/lib/python3.4/site-packages/requests/packages/urllib3/packages/six.py", line 685, in reraise
    raise value.with_traceback(tb)
  File "/usr/local/lib/python3.4/site-packages/requests/packages/urllib3/connectionpool.py", line 600, in urlopen
    chunked=chunked)
  File "/usr/local/lib/python3.4/site-packages/requests/packages/urllib3/connectionpool.py", line 356, in _make_request
    conn.request(method, url, **httplib_request_kw)
  File "/usr/local/lib/python3.4/http/client.py", line 1137, in request
    self._send_request(method, url, body, headers)
  File "/usr/local/lib/python3.4/http/client.py", line 1182, in _send_request
    self.endheaders(body)
  File "/usr/local/lib/python3.4/http/client.py", line 1133, in endheaders
    self._send_output(message_body)
  File "/usr/local/lib/python3.4/http/client.py", line 963, in _send_output
    self.send(msg)
  File "/usr/local/lib/python3.4/http/client.py", line 898, in send
    self.connect()
  File "/usr/local/lib/python3.4/site-packages/docker/unixconn/unixconn.py", line 41, in connect
    sock.connect(self.unix_socket)
requests.packages.urllib3.exceptions.ProtocolError: ('Connection aborted.', ConnectionRefusedError(111, 'Connection refused'))

My user has been added to the docker group and I've checked the owner of the file /var/run/docker.sock. It was root:docker. In a vain attempt to fix this I tried changing the owner of docker.dock to ubuntu, but that did not work. Unfortunately, searching for answers has not resulted in anything fruitful. All tips/comments/help will be super super appreciated!

Edit: I should add that I've run basic docker examples such as

docker run hello-world

and they do work ok.