diff --git a/bundles/wireguard/metadata.py b/bundles/wireguard/metadata.py
index e409e86..c9fd288 100644
--- a/bundles/wireguard/metadata.py
+++ b/bundles/wireguard/metadata.py
@@ -45,7 +45,7 @@ def peer_psks_and_iface_names(metadata):
 
     for peer_name in metadata.get('wireguard/peers', {}):
         peers[peer_name] = {
-            'iface': sub('[^a-z0-9-_]+', '_', peer_name)[:20],
+            'iface': sub('[^a-z0-9-_]+', '_', peer_name)[:12],
         }
 
         if node.name < peer_name: