diff --git a/requirements.txt b/requirements.txt
index 45f4494935..c765030dfe 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,7 +3,7 @@
 # process, which may cause wedges in the gate later.
 alembic>=0.8.10 # MIT
 pecan!=1.0.2,!=1.0.3,!=1.0.4,!=1.2,>=1.0.0 # BSD
-pbr>=2.0.0 # Apache-2.0
+pbr!=2.1.0,>=2.0.0 # Apache-2.0
 SQLAlchemy!=1.1.5,!=1.1.6,!=1.1.7,!=1.1.8,>=1.0.10 # MIT
 Babel!=2.4.0,>=2.3.4 # BSD
 eventlet!=0.18.3,>=0.18.2 # MIT