diff --git a/generators/input-validators/schema-site.yaml b/generators/input-validators/schema-site.yaml
index 740ee23fdae01283b914d7e49a4a7f28fc740053..3c58fd8e575080e286063672100265174c6391de 100644
--- a/generators/input-validators/schema-site.yaml
+++ b/generators/input-validators/schema-site.yaml
@@ -9,6 +9,7 @@ servers:
       serial: optional
       warranty: optional
       nodes: optional_hash
+      expire: optional
       network_adapters:
         <multi>:
           ip: ip_address