diff --git a/glance/async/flows/base_import.py b/glance/async/flows/base_import.py
index e884e96e74..b2676ed391 100644
--- a/glance/async/flows/base_import.py
+++ b/glance/async/flows/base_import.py
@@ -117,7 +117,8 @@ class _ImportToFS(task.Task):
         backend.register_opts(conf)
         conf.set_override('filesystem_store_datadir',
                           CONF.task.work_dir,
-                          group='glance_store')
+                          group='glance_store',
+                          enforce_type=True)
 
         # NOTE(flaper87): Do not even try to judge me for this... :(
         # With the glance_store refactor, this code will change, until
diff --git a/glance/tests/functional/db/test_simple.py b/glance/tests/functional/db/test_simple.py
index 8e978022b6..4c1d44871f 100644
--- a/glance/tests/functional/db/test_simple.py
+++ b/glance/tests/functional/db/test_simple.py
@@ -21,7 +21,8 @@ from glance.tests.functional.db import base
 
 
 def get_db(config):
-    CONF.set_override('data_api', 'glance.db.simple.api')
+    CONF.set_override('data_api', 'glance.db.simple.api',
+                      enforce_type=True)
     db_api = glance.db.get_api()
     return db_api
 
diff --git a/glance/tests/integration/v2/test_property_quota_violations.py b/glance/tests/integration/v2/test_property_quota_violations.py
index 8fdebd5cdb..25b65b1f45 100644
--- a/glance/tests/integration/v2/test_property_quota_violations.py
+++ b/glance/tests/integration/v2/test_property_quota_violations.py
@@ -70,7 +70,8 @@ class TestPropertyQuotaViolations(base.ApiTest):
         self.assertEqual(0, len(image_list))
 
         orig_property_quota = 10
-        CONF.set_override('image_property_quota', orig_property_quota)
+        CONF.set_override('image_property_quota', orig_property_quota,
+                          enforce_type=True)
 
         # Create an image (with deployer-defined properties)
         req_body = {'name': 'testimg',
diff --git a/glance/tests/unit/test_migrations.py b/glance/tests/unit/test_migrations.py
index 57b74bdb34..2a2a703756 100644
--- a/glance/tests/unit/test_migrations.py
+++ b/glance/tests/unit/test_migrations.py
@@ -538,7 +538,8 @@ class MigrationsMixin(test_migrations.WalkVersionsMixin):
 
     def test_legacy_parse_swift_uri_017(self):
         metadata_encryption_key = 'a' * 16
-        CONF.set_override('metadata_encryption_key', metadata_encryption_key)
+        CONF.set_override('metadata_encryption_key', metadata_encryption_key,
+                          enforce_type=True)
         self.addCleanup(CONF.reset)
         (legacy_parse_uri, encrypt_location) = from_migration_import(
             '017_quote_encrypted_swift_credentials', ['legacy_parse_uri',
@@ -553,7 +554,8 @@ class MigrationsMixin(test_migrations.WalkVersionsMixin):
 
     def _pre_upgrade_017(self, engine):
         metadata_encryption_key = 'a' * 16
-        CONF.set_override('metadata_encryption_key', metadata_encryption_key)
+        CONF.set_override('metadata_encryption_key', metadata_encryption_key,
+                          enforce_type=True)
         self.addCleanup(CONF.reset)
         images = db_utils.get_table(engine, 'images')
         unquoted = 'swift://acct:usr:pass@example.com/container/obj-id'