Use ansible_host instead of ansible_default_ip* for zk

Our zk config is a little too brittle. Let's just use the inventory
vars instead of detected network facts.

Change-Id: I288990edf587bc8394c9473388a858f46efb0691

playbooks/roles/nodepool-base/library/make_nodepool_zk_hosts.py

@@ -29,17 +29,8 @@ def main():
     zk_hosts = []
     try:
         for host in p['zk_group']:
-            hv = p['hostvars'][host]
-            if hv.get('ansible_default_ipv6'):
-                address=hv['ansible_default_ipv6']['address']
-            else:
-                if 'ansible_default_ipv4' not in hv:
-                    module.fail_json(
-                        msg="No network information facts found",
-                        changed=False)
-                address=hv['ansible_default_ipv4']['address']
             zk_hosts.append(dict(
-                host=address,
+                host=p['hostvars'][host]['ansible_host'],
                 port=2181
             ))
         module.exit_json(hosts=zk_hosts, changed=True)

playbooks/roles/nodepool-base/tasks/main.yaml

@@ -49,6 +49,8 @@
 
 # Have to run service-zookeeper before service-nodepool
 # because we need top populate the fact cache.
+# Also, we need IP addresses here because in the gate
+# hostnames do not resolve.
 - name: Get zk config
   make_nodepool_zk_hosts:
     hostvars: "{{ hostvars }}"