diff --git a/config.h b/config.h
index 05b3a5a..b6d9ae1 100644
--- a/config.h
+++ b/config.h
@@ -33,6 +33,7 @@
   struct in6_addr plat_subnet;
   char *default_pdp_interface;
   char *plat_from_dns64_hostname;
+  int use_dynamic_iid;
 };
 
 extern struct clat_config Global_Clatd_Config;