diff --git a/isisd/isis_zebra.c b/isisd/isis_zebra.c
index a385e6b..aff6a71 100644
--- a/isisd/isis_zebra.c
+++ b/isisd/isis_zebra.c
@@ -308,6 +308,7 @@
 
       stream_putw_at (stream, 0, stream_get_endp (stream));
       zclient_send_message(zclient);
+      SET_FLAG (route_info->flag, ISIS_ROUTE_FLAG_ZEBRA_SYNC);
     }
 }
 
@@ -328,6 +329,7 @@
       prefix4.prefix = prefix->u.prefix4;
       zapi_ipv4_route (ZEBRA_IPV4_ROUTE_DELETE, zclient, &prefix4, &api);
     }
+  UNSET_FLAG (route_info->flag, ISIS_ROUTE_FLAG_ZEBRA_SYNC);
 
   return;
 }