[CORD-1505]
Support multiple external interface names on compute nodes managed by VTN

Change-Id: I01f21a778bba60f8f040d714e4b3ec776557af19
diff --git a/roles/compute-node-config/templates/openstack-compute.yaml.j2 b/roles/compute-node-config/templates/openstack-compute.yaml.j2
index 0a4fb9c..6e76a43 100644
--- a/roles/compute-node-config/templates/openstack-compute.yaml.j2
+++ b/roles/compute-node-config/templates/openstack-compute.yaml.j2
@@ -25,7 +25,12 @@
 
 # OpenStack compute nodes
 {% for node in groups['compute'] %}
-{% if 'ipv4' in hostvars[node]['ansible_' ~ compute_external_interface] %}
+{% for ext_if in compute_external_interfaces %}
+{% set ansible_ext_if = 'ansible_' ~ ext_if | regex_replace('\W', '_') %}
+{% if hostvars[node][ansible_ext_if] is defined and 'ipv4' in hostvars[node][ansible_ext_if] %}
+{% set node_interface = hostvars[node][ansible_ext_if] %}
+
+# Compute node: {{ node }}, with interface {{ ansible_ext_if }}
     {{ hostvars[node]['ansible_hostname'] }}:
       type: tosca.nodes.Node
       requirements:
@@ -38,4 +43,5 @@
 
 {% endif %}
 {% endfor %}
+{% endfor %}