diff --git a/tox.ini b/tox.ini
index e6b664c9..7e6ba9f5 100644
--- a/tox.ini
+++ b/tox.ini
@@ -39,6 +39,8 @@ commands =
 
 [testenv:cover]
 basepython = python3
+setenv =
+    PYTHON=coverage run --source oslo_config --parallel-mode
 commands =
   coverage erase
   {[testenv]commands}