Comment 7 for bug 1649627

Looks like i found the reason:

Here [0] we have 2 openstack-network-routers task which apply the same manifests but twice - once on openstack-network configuration stage and the other on post deployment stage.

I reverted the environment with the bug and found that openstack_network/routers.pp was applied only one time. In puppet logs on primary controller I see that it was applied only once:

grep openstack_network/routers /var/log/puppet.log
2016-12-14 14:54:40 +0000 Scope(Class[Openstack_tasks::Openstack_network::Routers]) (notice): MODULAR: openstack_network/routers.pp

Then I applied manually openstack_network/routers.pp and external_gateway was correctly configured:

Notice: /Stage[main]/Openstack_tasks::Openstack_network::Routers/Neutron_router[router04]/gateway_network_name: gateway_network_name changed '' to 'admin_floating_net'

neutron router-list
+--------------------------------------+----------+------------------------------------------------------------------------------------------------------------------------------------+-------------+-------+
| id | name | external_gateway_info | distributed | ha |
+--------------------------------------+----------+------------------------------------------------------------------------------------------------------------------------------------+-------------+-------+
| 8f46bb7e-7192-4aae-981e-daed4cbdd239 | router04 | {"network_id": "90252123-b344-42e2-a08c-06a039e1596b", "enable_snat": true, "external_fixed_ips": [{"subnet_id": "e125106b-ebdc- | False | False |
| | | 4d4e-bb67-556c83da34f6", "ip_address": "10.109.39.131"}]} | | |
+--------------------------------------+----------+------------------------------------------------------------------------------------------------------------------------------------+-------------+-------+

[0] https://github.com/openstack/fuel-library/blob/master/deployment/puppet/openstack_tasks/examples/openstack-network/tasks.yaml#L189-L228