BVT failure: OSTF haproxy backends check fails due to neutron-server failure on secondary controllers: An unexpected error occurred in the NSX Plugin: Metadata initialization is incomplete on initializer node

Detailed bug description:
 Fuel NSXv plugin BVT fails due to OSTF check that verifies
 that all haproxy backend are in UP state. Currently neutron-servers
 on secondary controllers are not running due to exception.
 Neutron server tries to start before metadata infrastructure gets
 initialized and terminates. It does not run under pacemaker
 supervision, so it does not get restarted after metadata edges
 gets ready.

Steps to reproduce:
 Run nsxv_bvt.

Expected results:
 nsv_bvt passes.

Actual result:
 BVT fails:
AssertionError: Failed 1 OSTF tests; should fail 0 tests. Names of failed tests:
  - Check state of haproxy backends on controllers (failure) Some haproxy backend has down state.. Please refer to OpenStack logs for more details.
 neutron-server is not running on nodes with role "controller", "primary-controller"
 node is unaffected.

Reproducibility:
 100%

Workaround:
 N/A

Impact:
 Bug should be considered as CI blocker.

Description of the environment:
 Versions of components:
 Fuel 9.0 #418
 Fuel NSXv plugin 3.0 #509
 vCenter 5.5
 NSX Manager 6.2.0

Additional information:
 Neutron-server traceback: http://paste.openstack.org/show/506289/