diff --git a/modules/virtualMachine/variables.tf b/modules/virtualMachine/variables.tf
index e7dc32f..e41d869 100644
--- a/modules/virtualMachine/variables.tf
+++ b/modules/virtualMachine/variables.tf
@@ -26,7 +26,7 @@ variable "vm_domain" {
 variable "system_image_name" {
   description = "System image disk name"
   type = string
-  default = "${var.vm_shortname}.system"
+  default = "${local.shortname}.system"
 }
 
 variable "system_image_source" {
@@ -38,7 +38,7 @@ variable "system_image_source" {
 variable "data_image_name" {
   description = "Data image disk name"
   type = string
-  default = "${var.vm_shortname}.data"
+  default = "${local.shortname}.data"
 }
 
 variable "data_image_source" {