diff --git a/README.rst b/README.rst
index 1853de3..a459010 100644
--- a/README.rst
+++ b/README.rst
@@ -3,8 +3,8 @@ OpenStack Configuration
 =============================================
 
 This project contains Ansible playbooks and configuration of infrastructure on
-an existing OpenStack cloud for the OpenStack
-system.
+an existing OpenStack cloud for the OpenStack system. (Supported up to Yoga
+release.)
 
 Preparation
 ===========
diff --git a/requirements.yml b/requirements.yml
index 2dc411c..fda082e 100644
--- a/requirements.yml
+++ b/requirements.yml
@@ -9,3 +9,4 @@ roles:
 
 collections:
   - name: openstack.cloud
+    version: '<2'