diff --git a/src/lib/charm/openstack/tempest.py b/src/lib/charm/openstack/tempest.py
index b79e2d9..7c1a9db 100644
--- a/src/lib/charm/openstack/tempest.py
+++ b/src/lib/charm/openstack/tempest.py
@@ -6,6 +6,8 @@ import urllib
 
 import glanceclient
 import keystoneauth1
+import keystoneauth1.identity.v2 as keystoneauth1_v2
+import keystoneauth1.session as keystoneauth1_session
 import keystoneclient.v2_0.client as keystoneclient_v2
 import keystoneclient.v3.client as keystoneclient_v3
 import keystoneclient.auth.identity.v3 as keystone_id_v3
@@ -266,6 +268,17 @@ class TempestAdminAdapter(adapters.OpenStackRelationAdapter):
         """
         return service in self.get_present_services()
 
+    def get_nova_client(self):
+        if not self.keystone_session:
+            auth = keystoneauth1_v2.Password(
+                auth_url=self.keystone_auth_url(),
+                username=self.keystone_info['service_username'],
+                password=self.keystone_info['service_password'],
+                tenant_name=self.keystone_info['service_tenant_name'])
+            self.keystone_session = keystoneauth1_session.Session(auth=auth)
+        return novaclient_client.Client(
+            2, session=self.keystone_session)
+
     @property
     def compute_info(self):
         """Return flavor ids for user-defined flavors
@@ -274,17 +287,7 @@ class TempestAdminAdapter(adapters.OpenStackRelationAdapter):
         """
         compute_info = {}
         if self.service_present('nova'):
-            if self.keystone_session:
-                nova_client = novaclient_client.Client(
-                    2, session=self.keystone_session)
-            else:
-                nova_client = novaclient_client.Client(
-                    2,
-                    self.keystone_info['service_username'],
-                    self.keystone_info['service_password'],
-                    self.keystone_info['service_tenant_name'],
-                    self.keystone_auth_url(),
-                )
+            nova_client = self.get_nova_client()
             nova_ep = self.resolve_endpoint('compute', 'public')
             url = urllib.parse.urlparse(nova_ep)
             compute_info['nova_base'] = '{}://{}'.format(
diff --git a/src/tests/gate-basic-xenial-ocata b/src/tests/gate-basic-xenial-ocata
old mode 100644
new mode 100755
diff --git a/src/tests/gate-basic-zesty-ocata b/src/tests/gate-basic-zesty-ocata
old mode 100644
new mode 100755
diff --git a/src/tox.ini b/src/tox.ini
index 479d7bb..3bc4d0b 100644
--- a/src/tox.ini
+++ b/src/tox.ini
@@ -10,7 +10,7 @@ setenv = VIRTUAL_ENV={envdir}
          PYTHONHASHSEED=0
          AMULET_SETUP_TIMEOUT=2700
 whitelist_externals = juju
-passenv = HOME TERM AMULET_*
+passenv = HOME TERM AMULET_* CS_API_URL
 deps = -r{toxinidir}/test-requirements.txt
 install_command =
   pip install --allow-unverified python-apt {opts} {packages}