diff --git a/playbooks/groups/overcloud-config.yml b/playbooks/groups/overcloud-config.yml
index da3dac8c59..51edf3a7f5 100644
--- a/playbooks/groups/overcloud-config.yml
+++ b/playbooks/groups/overcloud-config.yml
@@ -30,7 +30,7 @@
       cloud: "{{ os_cloud }}"
       name: "{{item.name}}"
       ram: "{{item.ram}}"
-      root: "{{item.disk}}"
+      disk: "{{item.disk}}"
       vcpus: "{{item.vcpus}}"
       swap: "{{item.swap}}"
       ephemeral: 0