[nailgun][octane]Failed upgrade from 6.0 to 8.0 with GRE tunneling segmentation

[Nikita Zubkov]

Detailed bug description:
Controller upgrade fails if cluster deployed with GRE network segmentation

Nailgun traceback

Traceback (most recent call last):
  File "/usr/lib/python2.7/site-packages/nailgun/api/v1/handlers/base.py", line 284, in content_json
    resp = func(cls, *args, **kwargs)
  File "/usr/lib/python2.7/site-packages/nailgun/api/v1/handlers/orchestrator.py", line 83, in GET
    return self._serialize(cluster, nodes)
  File "/usr/lib/python2.7/site-packages/nailgun/api/v1/handlers/orchestrator.py", line 155, in _serialize
    graph, cluster, nodes, ignore_customized=True)
  File "/usr/lib/python2.7/site-packages/nailgun/orchestrator/deployment_serializers.py", line 605, in serialize
    cluster, nodes, ignore_customized=ignore_customized)
  File "/usr/lib/python2.7/site-packages/nailgun/orchestrator/deployment_serializers.py", line 85, in serialize
    cluster, node_group))
  File "/usr/lib/python2.7/site-packages/nailgun/orchestrator/deployment_serializers.py", line 94, in serialize_generated
    nodes = self.serialize_nodes(nodes)
  File "/usr/lib/python2.7/site-packages/nailgun/orchestrator/deployment_serializers.py", line 242, in serialize_nodes
    serialized_nodes.append(self.serialize_node(node, role))
  File "/usr/lib/python2.7/site-packages/nailgun/orchestrator/deployment_serializers.py", line 533, in serialize_node
    DeploymentHASerializer80, self).serialize_node(node, role)
  File "/usr/lib/python2.7/site-packages/nailgun/orchestrator/deployment_serializers.py", line 461, in serialize_node
    DeploymentHASerializer61, self).serialize_node(node, role)
  File "/usr/lib/python2.7/site-packages/nailgun/orchestrator/deployment_serializers.py", line 259, in serialize_node
    node_attrs.update(net_serializer.get_node_attrs(node))
  File "/usr/lib/python2.7/site-packages/nailgun/orchestrator/base_serializers.py", line 186, in get_node_attrs
    return cls.network_provider_node_attrs(node.cluster, node)
  File "/usr/lib/python2.7/site-packages/nailgun/orchestrator/neutron_serializers.py", line 64, in network_provider_node_attrs
    'network_scheme': cls.generate_network_scheme(node, networks),
  File "/usr/lib/python2.7/site-packages/nailgun/orchestrator/neutron_serializers.py", line 1052, in generate_network_scheme
    netgroup = nm.get_network_by_netname(ngname, networks)
  File "/usr/lib/python2.7/site-packages/nailgun/network/manager.py", line 869, in get_network_by_netname
    lambda n: n['name'] == netname, networks)[0]
IndexError: list index out of range

Steps to reproduce:
 1) Have MOS6.0 environment
 2) Upgrade master node (fuel 6.0) to 6.1 and then to 7.0
 3) Backup environment settings, following documented process
 4) Prepare new master node (fuel 8.0 MU2)
 5) Restore the backup from the third step
 5) Upgrade restored environment via Octane
 6) Upgrade primary controller via Octane

Expected results:
 Controller upgraded successfully

Actual result:
 Nailgun returns an error 500 which in turn breaks node upgrade.

Reproducibility:
 Use GRE network segmentation.

[Alexey Stupnikov (astupnikov)]

We no longer support MOS5.1, MOS6.0, MOS6.1
We deliver only Critical/Security fixes to MOS7.0, MOS8.0.
We deliver only High/Critical/Security fixes to MOS9.2.