diff --git a/doc/reference.conf b/doc/reference.conf
index 34c22e70..380fde7c 100644
--- a/doc/reference.conf
+++ b/doc/reference.conf
@@ -1399,6 +1399,11 @@ general {
 
 	/* oper_secure_only: require TLS on any connection trying to oper up */
 	oper_secure_only = no;
+
+	/* drain_reason: Message shown to users when they are rejected from a draining server.
+	 * requires extensions/drain to be loaded.
+	 */
+	drain_reason = "This server is not accepting connections.";
 };
 
 modules {