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[Alexandr Kostrikov]

The error in nailgun is:

2016-09-07 15:47:01.842 ERROR [7fe276b99880] (network_configuration) Serialization failed
Traceback (most recent call last):
  File "/usr/lib/python2.7/site-packages/nailgun/api/v1/handlers/network_configuration.py", line 92, in GET
    return self.serializer.serialize_for_cluster(cluster)
  File "/usr/lib/python2.7/site-packages/nailgun/objects/serializers/network_configuration.py", line 113, in serialize_for_cluster
    result['networking_parameters'] = cls.serialize_network_params(cluster)
  File "/usr/lib/python2.7/site-packages/nailgun/objects/serializers/network_configuration.py", line 106, in serialize_network_params
    if objects.Cluster.is_component_enabled(cluster, 'ironic'):
  File "/usr/lib/python2.7/site-packages/nailgun/objects/cluster.py", line 1440, in is_component_enabled
    return bool(instance.attributes.editable['additional_components'].
KeyError: 'additional_components'
2016-09-07 15:47:01.842 ERROR [7fe276b99880] (base) Unexpected exception occured
Traceback (most recent call last):
  File "/usr/lib/python2.7/site-packages/nailgun/api/v1/handlers/base.py", line 293, in handle_errors
    return func(cls, *args, **kwargs)
  File "<string>", line 2, in GET
  File "/usr/lib/python2.7/site-packages/nailgun/api/v1/handlers/base.py", line 351, in validate
    return func(cls, *args, **kwargs)
  File "<string>", line 2, in GET
  File "/usr/lib/python2.7/site-packages/nailgun/api/v1/handlers/base.py", line 377, in serialize
    resp = func(cls, *args, **kwargs)
  File "/usr/lib/python2.7/site-packages/nailgun/api/v1/handlers/network_configuration.py", line 92, in GET
    return self.serializer.serialize_for_cluster(cluster)
  File "/usr/lib/python2.7/site-packages/nailgun/objects/serializers/network_configuration.py", line 113, in serialize_for_cluster
    result['networking_parameters'] = cls.serialize_network_params(cluster)
  File "/usr/lib/python2.7/site-packages/nailgun/objects/serializers/network_configuration.py", line 106, in serialize_network_params
    if objects.Cluster.is_component_enabled(cluster, 'ironic'):
  File "/usr/lib/python2.7/site-packages/nailgun/objects/cluster.py", line 1440, in is_component_enabled
    return bool(instance.attributes.editable['additional_components'].
KeyError: 'additional_components'