diff --git a/tox.ini b/tox.ini
index 534cc65..57b5ead 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
 # We want to support both vanilla stdlib and eventlet monkey patched
 whitelist_externals = env
@@ -27,7 +27,7 @@ commands = {posargs}
 [testenv:docs]
 whitelist_externals = rm
 deps =
-  -c{env:UPPER_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.txt}
+  -c{env:TOX_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.txt}
   -r{toxinidir}/doc/requirements.txt
 commands =
   rm -fr doc/build