diff --git a/murano/tests/unit/api/cmd/test_test_runner.py b/murano/tests/unit/api/cmd/test_test_runner.py
index b6b0b635..500c8f30 100644
--- a/murano/tests/unit/api/cmd/test_test_runner.py
+++ b/murano/tests/unit/api/cmd/test_test_runner.py
@@ -56,7 +56,7 @@ class TestCaseShell(testtools.TestCase):
         CONF.clear()
 
     def override_config(self, name, override, group=None):
-        CONF.set_override(name, override, group)
+        CONF.set_override(name, override, group, enforce_type=True)
         self.addCleanup(CONF.clear_override, name, group)
 
     def shell(self, cmd_args=None, exitcode=0):
diff --git a/murano/tests/unit/base.py b/murano/tests/unit/base.py
index 6855f33c..abd65c19 100644
--- a/murano/tests/unit/base.py
+++ b/murano/tests/unit/base.py
@@ -30,7 +30,7 @@ class MuranoTestCase(testtools.TestCase):
         self.useFixture(fixtures.FakeLogger('murano'))
 
     def override_config(self, name, override, group=None):
-        CONF.set_override(name, override, group)
+        CONF.set_override(name, override, group, enforce_type=True)
         self.addCleanup(CONF.clear_override, name, group)
 
 
diff --git a/murano/tests/unit/db/migration/test_migrations_base.py b/murano/tests/unit/db/migration/test_migrations_base.py
index 0fc42787..e3342d20 100644
--- a/murano/tests/unit/db/migration/test_migrations_base.py
+++ b/murano/tests/unit/db/migration/test_migrations_base.py
@@ -55,14 +55,16 @@ class BaseWalkMigrationTestCase(object):
         should use oslo.config and openstack.commom.db.sqlalchemy.session with
         database functionality (reset default settings and session cleanup).
         """
-        CONF.set_override('connection', str(engine.url), group='database')
+        CONF.set_override('connection', str(engine.url), group='database',
+                          enforce_type=True)
 
     def _alembic_command(self, alembic_command, engine, *args, **kwargs):
         """Most of alembic command return data into output.
         We should redefine this setting for getting info.
         """
         self.ALEMBIC_CONFIG.stdout = buf = io.StringIO()
-        CONF.set_override('connection', str(engine.url), group='database')
+        CONF.set_override('connection', str(engine.url), group='database',
+                          enforce_type=True)
         getattr(command, alembic_command)(*args, **kwargs)
         res = buf.getvalue().strip()
         LOG.debug('Alembic command `{command}` returns: {result}'.format(
diff --git a/murano/tests/unit/engine/test_package_loader.py b/murano/tests/unit/engine/test_package_loader.py
index edade653..320de767 100644
--- a/murano/tests/unit/engine/test_package_loader.py
+++ b/murano/tests/unit/engine/test_package_loader.py
@@ -29,7 +29,8 @@ class TestCombinedPackageLoader(base.MuranoTestCase):
         super(TestCombinedPackageLoader, cls).setUpClass()
 
         location = os.path.dirname(__file__)
-        CONF.set_override('load_packages_from', [location], 'engine')
+        CONF.set_override('load_packages_from', [location], 'engine',
+                          enforce_type=True)
         cls.murano_client_factory = mock.MagicMock()
         cls.loader = package_loader.CombinedPackageLoader(
             cls.murano_client_factory, 'test_tenant_id')
diff --git a/murano/tests/unit/test_heat_stack.py b/murano/tests/unit/test_heat_stack.py
index 23dade4d..a37c7315 100644
--- a/murano/tests/unit/test_heat_stack.py
+++ b/murano/tests/unit/test_heat_stack.py
@@ -45,7 +45,8 @@ class TestHeatStack(base.MuranoTestCase):
         client_manager_mock.get_heat_client.return_value = \
             self.heat_client_mock
         self.environment_mock.clients = client_manager_mock
-        CONF.set_override('stack_tags', ['test-murano'], 'heat')
+        CONF.set_override('stack_tags', ['test-murano'], 'heat',
+                          enforce_type=True)
         self.mock_tag = ','.join(CONF.heat.stack_tags)
 
     @mock.patch(MOD_NAME + '.HeatStack._wait_state')
@@ -235,7 +236,8 @@ class TestHeatStack(base.MuranoTestCase):
 
         status_get.return_value = 'NOT_FOUND'
         wait_st.return_value = {}
-        CONF.set_override('stack_tags', ['test-murano', 'murano-tag'], 'heat')
+        CONF.set_override('stack_tags', ['test-murano', 'murano-tag'], 'heat',
+                          enforce_type=True)
         context = {constants.CTX_ENVIRONMENT: self.environment_mock}
 
         with helpers.contextual(context):