diff --git a/website/source/docs/builders/cloudstack.html.md b/website/source/docs/builders/cloudstack.html.md
index d33fb3763..b5bacb715 100644
--- a/website/source/docs/builders/cloudstack.html.md
+++ b/website/source/docs/builders/cloudstack.html.md
@@ -52,6 +52,7 @@ builder.
 
 -   `soure_iso` (string) - The name or ID of an ISO that will be mounted before
     booting the instance. This option is mutual exclusive with `source_template`.
+    When then is used `disk_offering` and `hypervisor` is required.
 
 -   `source_template` (string) - The name or ID of the template used as base
     template for the instance. This option is mutual explusive with `source_iso`.