diff --git a/src/client/src/tscServer.c b/src/client/src/tscServer.c
index 1f139ea2a5ad5c3d847a22e59c9c32a57198207b..7f6ad8c551fc3b501680b41ea14429f9e93da0e5 100644
--- a/src/client/src/tscServer.c
+++ b/src/client/src/tscServer.c
@@ -265,7 +265,10 @@ void *tscProcessMsgFromServer(char *msg, void *ahandle, void *thandle) {
 
   if (msg == NULL) {
     tscTrace("%p no response from ip:0x%x", pSql, pSql->ip);
-    pSql->index++;
+
+    // for single node situation, do NOT try next index
+    assert(pSql->index == 0);
+
     pSql->thandle = NULL;
 
     // todo taos_stop_query() in async model