diff --git a/defaults/main.yml b/defaults/main.yml
index 3ea215a..32fc69c 100644
--- a/defaults/main.yml
+++ b/defaults/main.yml
@@ -13,8 +13,10 @@ jupyter_hub_external_proxy_ips:
   - '127.0.0.1'
 
 jupyter_hub_trusted_alt_names:
-  - '127.0.0.1'
-  - 'localhost'
+  - 'IP:127.0.0.1'
+  - 'DNS:localhost'
+
+jupyter_hub_spawner_local_alt_names: True
 
 jupyter_hub_ip: '127.0.0.1'
 
diff --git a/templates/jupyterhub_config.py.j2 b/templates/jupyterhub_config.py.j2
index f80d576..7f06131 100644
--- a/templates/jupyterhub_config.py.j2
+++ b/templates/jupyterhub_config.py.j2
@@ -792,7 +792,7 @@ c.Spawner.default_url = ''
 #c.Spawner.ssl_alt_names = []
 
 ## Whether to include DNS:localhost, IP:127.0.0.1 in alt names
-#c.Spawner.ssl_alt_names_include_local = True
+c.Spawner.ssl_alt_names_include_local = {{ jupyter_hub_spawner_local_alt_names }}
 
 ## Timeout (in seconds) before giving up on starting of single-user server.
 #