diff --git a/extraconfig/post_deploy/undercloud_post.yaml b/extraconfig/post_deploy/undercloud_post.yaml
index ee2eded259..31649cd53e 100644
--- a/extraconfig/post_deploy/undercloud_post.yaml
+++ b/extraconfig/post_deploy/undercloud_post.yaml
@@ -119,7 +119,7 @@ resources:
         homedir: {get_param: UndercloudHomeDir}
         admin_password: {get_param: AdminPassword}
         snmp_readonly_user_password: {get_param: SnmpdReadonlyUserPassword}
-        enable_validations: [get_params: EnableValidations]
+        enable_validations: {get_param: EnableValidations}
         internal_tls_ca_file:
           if:
           - ca_file_enabled