diff --git a/debian/variables.tf b/debian/variables.tf
index 79def4e..5c268f2 100644
--- a/debian/variables.tf
+++ b/debian/variables.tf
@@ -59,5 +59,5 @@ variable "data_disk" {
 
 variable "fixed_address" {
   type = string
-  default = null
+  default = ""
 }