diff --git a/requirements.txt b/requirements.txt
index 19e7a80..0b8140c 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -6,7 +6,7 @@
 # __author__ = fla
 
 
-pbr>=0.11.1,<=1.8.1
+pbr>=0.11.1,<5.6.1
 
 python-openstackclient==1.9.0
 python-neutronclient==4.2.0