Add Network section for external-openstack-cloud-config's cloud.conf in templates

[Sryther]

What would you like to be added:

The "Network" parameters section in the template roles/kubernetes-apps/external_cloud_controller/openstack/templates/external-openstack-cloud-config.j2.

The content to add would look like this:

[Networking]
ipv6-support-disabled=false
internal-network-name=""
public-network-name=""

The default values could be changed in inventory/mycluster/group_vars/all/openstack.yml.

This is handled by kubernetes/cloud-provider-openstack since the v.14 (doc)

Documentation: https://github.com/kubernetes/cloud-provider-openstack/blob/master/docs/using-openstack-cloud-controller-manager.md#networking

Why is this needed:

I encountered issues in a fresh install with calico-node not being able to discover nodes because the Internal IP of nodes was provisioned wrongly by the DaemonSet openstack-cloud-controller-manager.

The addresses given to the nodes was simply all the IPs from OpenStack (public, private and IPv6 addresses) while we want only the true internal IPs.

After adding manually the Network section in the external-openstack-cloud-config Secret and reloading the openstack-cloud-controller-manager, the nodes had the right Internal IPs in their Addresses.

Without this improvement we have extra steps to configure the cluster while we think it'll work seamlessly.

Sorry for my english :)

[floryut]

@Sryther Thanks for finding this, are you available to submit a PR ?

[Sryther]

This issue (cloud-provider-openstack/issues/407) is related to what could happen if we omit this configuration.