diff --git a/tox.ini b/tox.ini
index 2545408..869ac25 100644
--- a/tox.ini
+++ b/tox.ini
@@ -14,6 +14,8 @@ deps =
   -c{env:UPPER_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.txt}
   -r{toxinidir}/test-requirements.txt
   -r{toxinidir}/requirements.txt
+whitelist_externals =
+  rm
 commands = rm -f .testrepository/times.dbm
            stestr --test-path=./watcherclient/tests/unit run {posargs}
            stestr slowest