diff --git a/modules/openstack_project/files/puppetmaster/expand-groups.sh b/modules/openstack_project/files/puppetmaster/expand-groups.sh
index bd860f56aa..678ce0d45c 100644
--- a/modules/openstack_project/files/puppetmaster/expand-groups.sh
+++ b/modules/openstack_project/files/puppetmaster/expand-groups.sh
@@ -20,6 +20,10 @@ trap "rm -rf $outdir" EXIT
 outfile=$outdir/generated-groups
 echo "# This file is autogenerated" > $outfile
 
+# Protect against leaky environment settings
+unset OS_CLOUD
+unset OS_REGION_NAME
+
 IFS=$'\n'
 for line in $(</etc/ansible/groups.txt); do
     name=$(echo $line | cut -f1 -d' ')