Access to dashboard fails using ip address after installation by foreman

Issue

• Installed Openstack Controller using foreman. Accessing dashboard is successful using fqdn of controller, but fails to access with ip address with below error.

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• /var/log/horizon/horizon.log shows below error.

Traceback (most recent call last):
  File "/usr/lib/python2.6/site-packages/django/core/handlers/base.py", line 89, in get_response
    response = middleware_method(request)
  File "/usr/lib/python2.6/site-packages/django/middleware/common.py", line 55, in process_request
    host = request.get_host()
  File "/usr/lib/python2.6/site-packages/django/http/__init__.py", line 223, in get_host
    "Invalid HTTP_HOST header (you may need to set ALLOWED_HOSTS): %s" % host)
SuspiciousOperation: Invalid HTTP_HOST header (you may need to set ALLOWED_HOSTS): 10.65.216.20