diff --git a/tox.ini b/tox.ini
index 7067c7c..d0d4ce2 100644
--- a/tox.ini
+++ b/tox.ini
@@ -6,7 +6,7 @@ ignore_basepython_conflict = true
 [testenv]
 basepython = python3
 deps =
-  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+  -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
   -r{toxinidir}/test-requirements.txt
 commands = stestr run --slowest {posargs}
 
@@ -23,7 +23,7 @@ commands = {posargs}
 [testenv:docs]
 whitelist_externals = rm
 deps =
-  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+  -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
   -r{toxinidir}/doc/requirements.txt
 commands =
   rm -fr doc/build