diff --git a/tox.ini b/tox.ini
index a104b9112..5e1c6b8e2 100644
--- a/tox.ini
+++ b/tox.ini
@@ -45,7 +45,7 @@ deps = -r{toxinidir}/requirements.txt
 commands = {posargs}
 
 [flake8]
-ignore = H301,H506
+ignore = H301
 builtins = _
 exclude=.venv,.git,.tox,dist,doc,./ceilometer/openstack/common,*lib/python*,*egg,tools,nova_tests,build
 show-source = True