diff --git a/zaza/openstack/utilities/openstack.py b/zaza/openstack/utilities/openstack.py
index f0b7ffc..1e533d4 100644
--- a/zaza/openstack/utilities/openstack.py
+++ b/zaza/openstack/utilities/openstack.py
@@ -610,7 +610,7 @@ def configure_gateway_ext_port(novaclient, neutronclient,
                                     net_id=None, fixed_ip=None)
             if add_dataport_to_netplan:
                 add_interface_to_netplan(server.name,
-                                         mac_address=port['mac_address'],
+                                         mac_address=get_mac_from_port(port),
                                          dvr_mode=dvr_mode)
     ext_br_macs = []
     for port in neutronclient.list_ports(network_id=net_id)['ports']:
@@ -640,6 +640,19 @@ def configure_gateway_ext_port(novaclient, neutronclient,
         juju_wait.wait(wait_for_workload=True)
 
 
+@tenacity.retry(wait=tenacity.wait_exponential(multiplier=1, max=60),
+                reraise=True, retry=tenacity.retry_if_exception_type(KeyError))
+def get_mac_from_port(port):
+    """Get mac address from port, with tenacity due to openstack async.
+
+    :param port: neutron port
+    :type port: neutron port
+    :returns: mac address
+    :rtype: string
+    """
+    return port['mac_address']
+
+
 def create_project_network(neutron_client, project_id, net_name='private',
                            shared=False, network_type='gre', domain=None):
     """Create the project network.