diff --git a/vars.tf b/vars.tf
index f295949..47a4949 100644
--- a/vars.tf
+++ b/vars.tf
@@ -86,7 +86,7 @@ variable "nodes" {
       nic_name     = string
       bridge       = string
       ip           = string
-      nameserver   = string
+      nameserver   = optional(string)
       gw           = string
     })), {})
     machines = optional(map(object({