diff --git a/matter_door_lock.py b/matter_door_lock.py
index 75cb5b6..000f5c9 100755
--- a/matter_door_lock.py
+++ b/matter_door_lock.py
@@ -148,7 +148,7 @@ async def main(args: Sequence[str] | None = None) -> None:
         dest="websocketUrl",
         action="store",
         type=str,
-        default="ws://localhost:5580/ws",
+        default="ws://core-matter-server:5580/ws",
     )
     prog.add_argument(
         "--timeout",