diff --git a/hooks/glance_utils.py b/hooks/glance_utils.py
index f9b66dcb..a33bce63 100644
--- a/hooks/glance_utils.py
+++ b/hooks/glance_utils.py
@@ -25,7 +25,6 @@ from charmhelpers.core.hookenv import (
     log,
     relation_ids,
     service_name,
-    status_get,
 )
 
 
@@ -61,7 +60,6 @@ from charmhelpers.contrib.openstack.utils import (
     git_pip_venv_dir,
     configure_installation_source,
     os_release,
-    set_os_workload_status,
     is_unit_paused_set,
     make_assess_status_func,
     pause_unit,
@@ -442,28 +440,45 @@ def git_post_install(projects_yaml):
         service_restart('glance-registry')
 
 
-def check_optional_relations(configs):
-    required_interfaces = {}
+def get_optional_interfaces():
+    """Return the optional interfaces that should be checked if the relavent
+    relations have appeared.
+
+    :returns: {general_interface: [specific_int1, specific_int2, ...], ...}
+    """
+    optional_interfaces = {}
+    if relation_ids('ha'):
+        optional_interfaces['ha'] = ['cluster']
+
+    if relation_ids('ceph') or relation_ids('object-store'):
+        optional_interfaces['storage-backend'] = ['ceph', 'object-store']
+
+    if relation_ids('amqp'):
+        optional_interfaces['messaging'] = ['amqp']
+    return optional_interfaces
+
+
+def check_optional_relations(configs):
+    """Check that if we have a relation_id for high availability that we can
+    get the hacluster config.  If we can't then we are blocked.
+
+    This function is called from assess_status/set_os_workload_status as the
+    charm_func and needs to return either None, None if there is no problem or
+    the status, message if there is a problem.
+
+    :param configs: an OSConfigRender() instance.
+    :return 2-tuple: (string, string) = (status, message)
+    """
     if relation_ids('ha'):
-        required_interfaces['ha'] = ['cluster']
         try:
             get_hacluster_config()
         except:
             return ('blocked',
                     'hacluster missing configuration: '
                     'vip, vip_iface, vip_cidr')
-
-    if relation_ids('ceph') or relation_ids('object-store'):
-        required_interfaces['storage-backend'] = ['ceph', 'object-store']
-
-    if relation_ids('amqp'):
-        required_interfaces['messaging'] = ['amqp']
-
-    if required_interfaces:
-        set_os_workload_status(configs, required_interfaces)
-        return status_get()
-    else:
-        return 'unknown', 'No optional relations'
+    # return 'unknown' as the lowest priority to not clobber an existing
+    # status.
+    return "unknown", ""
 
 
 def swift_temp_url_key():
@@ -529,14 +544,20 @@ def assess_status_func(configs):
     Used directly by assess_status() and also for pausing and resuming
     the unit.
 
+    NOTE: REQUIRED_INTERFACES is augmented with the optional interfaces
+    depending on the current config before being passed to the
+    make_assess_status_func() function.
+
     NOTE(ajkavanagh) ports are not checked due to race hazards with services
     that don't behave sychronously w.r.t their service scripts.  e.g.
     apache2.
     @param configs: a templating.OSConfigRenderer() object
     @return f() -> None : a function that assesses the unit's workload status
     """
+    required_interfaces = REQUIRED_INTERFACES.copy()
+    required_interfaces.update(get_optional_interfaces())
     return make_assess_status_func(
-        configs, REQUIRED_INTERFACES,
+        configs, required_interfaces,
         charm_func=check_optional_relations,
         services=services(), ports=None)
 
diff --git a/unit_tests/test_glance_utils.py b/unit_tests/test_glance_utils.py
index ff84aaa2..713ae953 100644
--- a/unit_tests/test_glance_utils.py
+++ b/unit_tests/test_glance_utils.py
@@ -295,18 +295,23 @@ class TestGlanceUtils(CharmTestCase):
             asf.assert_called_once_with('test-config')
             callee.assert_called_once_with()
 
+    @patch.object(utils, 'get_optional_interfaces')
     @patch.object(utils, 'REQUIRED_INTERFACES')
     @patch.object(utils, 'services')
     @patch.object(utils, 'make_assess_status_func')
     def test_assess_status_func(self,
                                 make_assess_status_func,
                                 services,
-                                REQUIRED_INTERFACES):
+                                REQUIRED_INTERFACES,
+                                get_optional_interfaces):
         services.return_value = 's1'
+        REQUIRED_INTERFACES.copy.return_value = {'int': ['test 1']}
+        get_optional_interfaces.return_value = {'opt': ['test 2']}
         utils.assess_status_func('test-config')
         # ports=None whilst port checks are disabled.
         make_assess_status_func.assert_called_once_with(
-            'test-config', REQUIRED_INTERFACES,
+            'test-config',
+            {'int': ['test 1'], 'opt': ['test 2']},
             charm_func=utils.check_optional_relations,
             services='s1', ports=None)