Get IP addresses of neutron subports

Vlan-aware VMs are commonly used in telecom.
Those VMs are plugged into flat networks and use neutron trunk.
https://docs.openstack.org/neutron/latest/admin/config-trunking.html

Currenlty, getAttachedInterfacesByID() only returns neutron ports directly attached to VM.
For vlan-aware VMs, IP addresses are assigned on neutron subports.
Subports are attached to the trunk; they are not attached to the VM directly.
This pull request changes getAttachedInterfacesByID() to return IP addresses of neutron subports when they exist.
Without this change, Kubernetes is unable to IP addresses of vlan-aware VMs.
This change is transparent to VMs noting using neturon trunk.

Signed-off-by: Jing Zhang <[email protected]>

Author: Jing Zhang

pkg/openstack/instances.go

@@ -154,7 +154,7 @@ func (os *OpenStack) instances() (*Instances, bool) {
 
 	network, err := client.NewNetworkV2(os.provider, os.epOpts)
 	if err != nil {
-		klog.Errorf("Failed to create an OpenStack Network client: %v", err)
+		klog.Errorf("unable to access network v2 API : %v", err)
 		return nil, false
 	}