diff --git a/tobiko/openstack/stacks/_neutron.py b/tobiko/openstack/stacks/_neutron.py
index f31036b73..7dbd96cff 100644
--- a/tobiko/openstack/stacks/_neutron.py
+++ b/tobiko/openstack/stacks/_neutron.py
@@ -48,7 +48,7 @@ class ExternalNetworkStackFixture(heat.HeatStackFixture):
     def external_name(self):
         return tobiko.tobiko_config().neutron.external_network
 
-    subnet_enable_dhcp: typing.Optional[bool] = True
+    subnet_enable_dhcp: typing.Optional[bool] = None
 
     _external_network: typing.Optional[NeutronNetworkType] = None
 
@@ -74,6 +74,11 @@ class ExternalNetworkStackFixture(heat.HeatStackFixture):
                 network_dump = json.dumps(network, indent=4, sort_keys=True)
                 LOG.debug(f"Found external network for {self.fixture_name}:\n"
                           f"{network_dump}")
+
+                subnets = neutron.list_subnets(network_id=network['id'])
+                subnets_dump = json.dumps(subnets, indent=4, sort_keys=True)
+                LOG.debug(f"External subnets for {self.fixture_name}:\n"
+                          f"{subnets_dump}")
                 self._external_network = external_network = network
                 break
             else:
diff --git a/tobiko/tests/functional/openstack/stacks/test_neutron.py b/tobiko/tests/functional/openstack/stacks/test_neutron.py
index eee648a62..e1bfc3aa1 100644
--- a/tobiko/tests/functional/openstack/stacks/test_neutron.py
+++ b/tobiko/tests/functional/openstack/stacks/test_neutron.py
@@ -111,8 +111,7 @@ class ExternalNetworkStackTest(testtools.TestCase):
         self.assertTrue(network['id'])
         self.assertIs(True, network['router:external'])
         self.assertEqual('ACTIVE', network['status'])
-        subnets = neutron.list_subnets(network_id=network['id'],
-                                       enable_dhcp=True)
+        subnets = neutron.list_subnets(network_id=network['id'])
         self.assertNotEqual([], subnets)
 
     def test_has_external_network(self):