python - マネージド サービス ID (MSI) を使用して VM で Python アプリケーションを認証する

Question

以下のリンクで提供されている MSI の例を使用しようとしています。

https://docs.microsoft.com/en-us/python/azure/python-sdk-azure-authenticate?view=azure-python#mgmt-auth-msi

そのために、Linux VM を作成し、そこに MSI 拡張機能をインストールし、Python アプリケーションで上記のコードを実行しました。その Python アプリケーションを実行すると、次のエラーが発生します。

[azureuser@vish-redhat ~]$ python msi-auth.py 
No handlers could be found for logger "msrestazure.azure_active_directory"
Traceback (most recent call last):
  File "msi-auth.py", line 10, in <module>
    subscription = next(subscription_client.subscriptions.list())
  File "/usr/lib/python2.7/site-packages/msrest/paging.py", line 121, in __next__
    self.advance_page()
  File "/usr/lib/python2.7/site-packages/msrest/paging.py", line 107, in advance_page
    self._response = self._get_next(self.next_link)
  File "/usr/lib/python2.7/site-packages/azure/mgmt/resource/subscriptions/v2016_06_01/operations/subscriptions_operations.py", line 207, in internal_paging
    request, header_parameters, **operation_config)
  File "/usr/lib/python2.7/site-packages/msrest/service_client.py", line 191, in send
    session = self.creds.signed_session()
  File "/usr/lib/python2.7/site-packages/msrestazure/azure_active_directory.py", line 685, in signed_session
    self.set_token()
  File "/usr/lib/python2.7/site-packages/msrestazure/azure_active_directory.py", line 681, in set_token
    self.scheme, _, self.token = get_msi_token(self.resource, self.port, self.msi_conf)
  File "/usr/lib/python2.7/site-packages/msrestazure/azure_active_directory.py", line 590, in get_msi_token
    result = requests.post(request_uri, data=payload, headers={'Metadata': 'true'})
  File "/usr/lib/python2.7/site-packages/requests/api.py", line 108, in post
    return request('post', url, data=data, json=json, **kwargs)
  File "/usr/lib/python2.7/site-packages/requests/api.py", line 50, in request
    response = session.request(method=method, url=url, **kwargs)
  File "/usr/lib/python2.7/site-packages/requests/sessions.py", line 464, in request
    resp = self.send(prep, **send_kwargs)
  File "/usr/lib/python2.7/site-packages/requests/sessions.py", line 576, in send
    r = adapter.send(request, **kwargs)
  File "/usr/lib/python2.7/site-packages/requests/adapters.py", line 415, in send
    raise ConnectionError(err, request=request)
requests.exceptions.ConnectionError: ('Connection aborted.', error(111, 'Connection refused'))
[azureuser@vish-redhat ~]$ 

コード：

from msrestazure.azure_active_directory import MSIAuthentication
from azure.mgmt.resource import ResourceManagementClient, SubscriptionClient

# Create MSI Authentication
credentials = MSIAuthentication()


# Create a Subscription Client
subscription_client = SubscriptionClient(credentials)
subscription = next(subscription_client.subscriptions.list())
subscription_id = subscription.subscription_id

# Create a Resource Management client
resource_client = ResourceManagementClient(credentials, subscription_id)


# List resource groups as an example. The only limit is what role and policy are assigned to this MSI token.
for resource_group in resource_client.resource_groups.list():
    print(resource_group.name)