Check if backends are up

lb-common/overlay/opt/frontend/config/common/haproxy_swamid.j2

@@ -27,3 +27,12 @@ frontend {{ site_name }}
     use_backend {{ site_name }}__default
     {% endblock usebackend %}
 {% endblock frontend %}
+{% block backend %}
+{{ output_backends(backends,
+      config=[
+      'cookie SERVERID insert indirect nocache',
+      'option httpchk'
+      ]
+   )
+}}
+{% endblock backend %}