diff --git a/au_test_harness/au_worker.py b/au_test_harness/au_worker.py
index 981cde5..7b2c3c6 100644
--- a/au_test_harness/au_worker.py
+++ b/au_test_harness/au_worker.py
@@ -192,7 +192,7 @@
     cache_path = self.update_cache.get(update_id)
     if cache_path:
       update_url = dev_server_wrapper.DevServerWrapper.GetDevServerURL(
-          proxy_port, cache_path)
+          port=proxy_port, sub_dir=cache_path)
       cmd.append('--update_url=%s' % update_url)
     else:
       raise update_exception.UpdateException(
diff --git a/au_test_harness/cros_au_test_harness.py b/au_test_harness/cros_au_test_harness.py
index 014884b..54bee7f 100755
--- a/au_test_harness/cros_au_test_harness.py
+++ b/au_test_harness/cros_au_test_harness.py
@@ -215,7 +215,7 @@
       # Only start a devserver if we'll need it.
       if update_cache:
         my_server = dev_server_wrapper.DevServerWrapper(
-            options.test_results_root)
+            log_dir=options.test_results_root)
         my_server.Start()
 
       if options.type == 'vm' and options.parallel: