diff --git a/src/vnet/devices/tap/tapv2.api b/src/vnet/devices/tap/tapv2.api
index dee7304..c11a07c 100644
--- a/src/vnet/devices/tap/tapv2.api
+++ b/src/vnet/devices/tap/tapv2.api
@@ -55,7 +55,7 @@
 {
   u32 client_index;
   u32 context;
-  u32 id;
+  u32 id [default= 0xffffffff] ;
   u8 use_random_mac;
   u8 mac_address[6];
   u16 tx_ring_sz; /* optional, default is 256 entries, must be power of 2 */