diff --git a/zaza/openstack/charm_tests/ceph/tests.py b/zaza/openstack/charm_tests/ceph/tests.py
index 9e18ca872..86fcf33c9 100644
--- a/zaza/openstack/charm_tests/ceph/tests.py
+++ b/zaza/openstack/charm_tests/ceph/tests.py
@@ -1815,9 +1815,9 @@ def test_key_rotate(self):
 
         try:
             zaza_model.get_application('ceph-fs')
-            fs_entity = self._get_all_keys(unit, lambda x: x.startswith('mds.'))
-            if fs_entity is not None:
-                self._check_key_rotation(next(iter(fs_entity))[0], unit)
+            fs_svc = self._get_all_keys(unit, lambda x: x.startswith('mds.'))
+            if fs_svc is not None:
+                self._check_key_rotation(next(iter(fs_svc))[0], unit)
             else:
                 logging.info('ceph-fs units present, but no MDS service')
         except KeyError: