diff --git a/requirements.txt b/requirements.txt
index 70c84fe..8f3093e 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,7 +2,7 @@
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
 
-pbr>=2.0.0,!=2.1.0  # Apache-2.0
-oslotest>=1.10.0  # Apache-2.0
-tempest>=17.1.0  # Apache-2.0
-tenacity>=3.2.1  # Apache-2.0
+pbr!=2.1.0,>=2.0.0 # Apache-2.0
+oslotest>=1.10.0 # Apache-2.0
+tempest>=17.1.0 # Apache-2.0
+tenacity>=3.2.1 # Apache-2.0