diff --git a/src/rpc/src/rpcMain.c b/src/rpc/src/rpcMain.c
index fa46c3a0f35aaa8076815bf6f7de6d8f802f590b..405f796a5e2e281ee5a63bf3fed7c14426ac30b4 100644
--- a/src/rpc/src/rpcMain.c
+++ b/src/rpc/src/rpcMain.c
@@ -124,8 +124,7 @@ typedef struct SRpcConn {
 } SRpcConn;
 
 int tsRpcMaxUdpSize = 15000;  // bytes
-int tsRpcProgressTime = 10;  // milliseocnds
-
+int tsProgressTimer = 100;
 // not configurable
 int tsRpcMaxRetry;
 int tsRpcHeadSize;
@@ -204,7 +203,8 @@ static void  rpcUnlockConn(SRpcConn *pConn);
 void *rpcOpen(const SRpcInit *pInit) {
   SRpcInfo *pRpc;
 
-  tsRpcMaxRetry = tsRpcMaxTime * 1000 / tsRpcProgressTime;
+  tsProgressTimer = tsRpcTimer/2; 
+  tsRpcMaxRetry = tsRpcMaxTime * 1000/tsProgressTimer;
   tsRpcHeadSize = RPC_MSG_OVERHEAD; 
   tsRpcOverhead = sizeof(SRpcReqContext);
 
@@ -420,8 +420,11 @@ void rpcSendResponse(const SRpcMsg *pRsp) {
   pConn->rspMsgLen = msgLen;
   if (pMsg->code == TSDB_CODE_ACTION_IN_PROGRESS) pConn->inTranId--;
 
+  SRpcInfo *pRpc = pConn->pRpc;
   taosTmrStopA(&pConn->pTimer);
-  // taosTmrReset(rpcProcessIdleTimer, pRpc->idleTime, pConn, pRpc->tmrCtrl, &pConn->pIdleTimer);
+
+  // set the idle timer to monitor the activity
+  taosTmrReset(rpcProcessIdleTimer, pRpc->idleTime, pConn, pRpc->tmrCtrl, &pConn->pIdleTimer);
   rpcSendMsgToPeer(pConn, msg, msgLen);
   pConn->secured = 1; // connection shall be secured
 
@@ -683,6 +686,7 @@ static SRpcConn *rpcSetupConnToServer(SRpcReqContext *pContext) {
     tError("%s %p, failed to set up connection(%s)", pRpc->label, pContext->ahandle, tstrerror(terrno));
   }
 
+  pConn->tretry = 0;
   return pConn;
 }
 
@@ -748,20 +752,28 @@ static int rpcProcessRspHead(SRpcConn *pConn, SRpcHead *pHead) {
   taosTmrStopA(&pConn->pTimer);
   pConn->retry = 0;
 
+  if (pHead->code == TSDB_CODE_AUTH_REQUIRED && pRpc->spi) {
+    tTrace("%s, authentication shall be restarted", pConn->info);
+    pConn->secured = 0;
+    rpcSendMsgToPeer(pConn, pConn->pReqMsg, pConn->reqMsgLen);      
+    pConn->pTimer = taosTmrStart(rpcProcessRetryTimer, tsRpcTimer, pConn, pRpc->tmrCtrl);
+    return TSDB_CODE_ALREADY_PROCESSED;
+  }
+
   if (pHead->code == TSDB_CODE_ACTION_IN_PROGRESS) {
     if (pConn->tretry <= tsRpcMaxRetry) {
-      tTrace("%s, peer is still processing the transaction", pConn->info);
+      tTrace("%s, peer is still processing the transaction, retry:%d", pConn->info, pConn->tretry);
       pConn->tretry++;
       rpcSendReqHead(pConn);
-      taosTmrReset(rpcProcessRetryTimer, tsRpcTimer, pConn, pRpc->tmrCtrl, &pConn->pTimer);
+      pConn->pTimer = taosTmrStart(rpcProcessRetryTimer, tsRpcTimer, pConn, pRpc->tmrCtrl);
       return TSDB_CODE_ALREADY_PROCESSED;
     } else {
       // peer still in processing, give up
-      return TSDB_CODE_TOO_SLOW;
+      tTrace("%s, server processing takes too long time, give up", pConn->info);
+      pHead->code = TSDB_CODE_TOO_SLOW;
     }
   }
 
-  pConn->tretry = 0;
   pConn->outType = 0;
   pConn->pReqMsg = NULL;
   pConn->reqMsgLen = 0;
@@ -820,7 +832,9 @@ static SRpcConn *rpcProcessMsgHead(SRpcInfo *pRpc, SRecvInfo *pRecv) {
     if ( rpcIsReq(pHead->msgType) ) {
       terrno = rpcProcessReqHead(pConn, pHead);
       pConn->connType = pRecv->connType;
-      taosTmrReset(rpcProcessIdleTimer, pRpc->idleTime, pConn, pRpc->tmrCtrl, &pConn->pIdleTimer);
+
+      // client shall send the request within tsRpcTime again, put 20 mseconds tolerance
+      taosTmrReset(rpcProcessIdleTimer, tsRpcTimer+20, pConn, pRpc->tmrCtrl, &pConn->pIdleTimer);
     } else {
       terrno = rpcProcessRspHead(pConn, pHead);
     }
@@ -935,7 +949,7 @@ static void rpcProcessIncomingMsg(SRpcConn *pConn, SRpcHead *pHead) {
    
   if ( rpcIsReq(pHead->msgType) ) {
     rpcMsg.handle = pConn;
-    taosTmrReset(rpcProcessProgressTimer, tsRpcTimer/2, pConn, pRpc->tmrCtrl, &pConn->pTimer);
+    pConn->pTimer = taosTmrStart(rpcProcessProgressTimer, tsProgressTimer, pConn, pRpc->tmrCtrl);
     (*(pRpc->cfp))(&rpcMsg, NULL);
   } else {
     // it's a response
@@ -943,14 +957,12 @@ static void rpcProcessIncomingMsg(SRpcConn *pConn, SRpcHead *pHead) {
     rpcMsg.handle = pContext->ahandle;
     pConn->pContext = NULL;
 
-    if (pHead->code == TSDB_CODE_AUTH_REQUIRED) {
-      pConn->secured = 0;
-      rpcSendReqToServer(pRpc, pContext);
-      return;
-    }
-
     // for UDP, port may be changed by server, the port in ipSet shall be used for cache
-    rpcAddConnIntoCache(pRpc->pCache, pConn, pConn->peerFqdn, pContext->ipSet.port[pContext->ipSet.inUse], pConn->connType);    
+    if (pHead->code != TSDB_CODE_TOO_SLOW) {
+      rpcAddConnIntoCache(pRpc->pCache, pConn, pConn->peerFqdn, pContext->ipSet.port[pContext->ipSet.inUse], pConn->connType);    
+    } else {
+      rpcCloseConn(pConn);
+    }
 
     if (pHead->code == TSDB_CODE_REDIRECT) { 
       pContext->redirect++;
@@ -1039,6 +1051,7 @@ static void rpcSendErrorMsgToPeer(SRecvInfo *pRecv, int32_t code) {
   pReplyHead->sourceId = pRecvHead->destId;
   pReplyHead->destId = pRecvHead->sourceId;
   pReplyHead->linkUid = pRecvHead->linkUid;
+  pReplyHead->ahandle = pRecvHead->ahandle;
 
   pReplyHead->code = htonl(code);
   msgLen = sizeof(SRpcHead);
@@ -1095,8 +1108,8 @@ static void rpcSendReqToServer(SRpcInfo *pRpc, SRpcReqContext *pContext) {
   pConn->reqMsgLen = msgLen;
   pConn->pContext = pContext;
 
-  taosTmrReset(rpcProcessRetryTimer, tsRpcTimer, pConn, pRpc->tmrCtrl, &pConn->pTimer);
   rpcSendMsgToPeer(pConn, msg, msgLen);
+  taosTmrReset(rpcProcessRetryTimer, tsRpcTimer, pConn, pRpc->tmrCtrl, &pConn->pTimer);
 
   rpcUnlockConn(pConn);
 }
@@ -1172,7 +1185,7 @@ static void rpcProcessRetryTimer(void *param, void *tmrId) {
     if (pConn->retry < 4) {
       tTrace("%s, re-send msg:%s to %s:%hu", pConn->info, taosMsg[pConn->outType], pConn->peerFqdn, pConn->peerPort);
       rpcSendMsgToPeer(pConn, pConn->pReqMsg, pConn->reqMsgLen);      
-      taosTmrReset(rpcProcessRetryTimer, tsRpcTimer, pConn, pRpc->tmrCtrl, &pConn->pTimer);
+      pConn->pTimer = taosTmrStart(rpcProcessRetryTimer, tsRpcTimer, pConn, pRpc->tmrCtrl);
     } else {
       // close the connection
       tTrace("%s, failed to send msg:%s to %s:%hu", pConn->info, taosMsg[pConn->outType], pConn->peerFqdn, pConn->peerPort);
@@ -1225,7 +1238,7 @@ static void rpcProcessProgressTimer(void *param, void *tmrId) {
   if (pConn->inType && pConn->user[0]) {
     tTrace("%s, progress timer expired, send progress", pConn->info);
     rpcSendQuickRsp(pConn, TSDB_CODE_ACTION_IN_PROGRESS);
-    taosTmrReset(rpcProcessProgressTimer, tsRpcTimer/2, pConn, pRpc->tmrCtrl, &pConn->pTimer);
+    pConn->pTimer = taosTmrStart(rpcProcessProgressTimer, tsProgressTimer, pConn, pRpc->tmrCtrl);
   } else {
     tTrace("%s, progress timer:%p not processed", pConn->info, tmrId);
   }
@@ -1357,15 +1370,17 @@ static int rpcCheckAuthentication(SRpcConn *pConn, char *msg, int msgLen) {
   if ((pConn->secured && pHead->spi == 0) || (pHead->spi == 0 && pConn->spi == 0)){
     // secured link, or no authentication 
     pHead->msgLen = (int32_t)htonl((uint32_t)pHead->msgLen);
+    // tTrace("%s, secured link, no auth is required", pConn->info);
     return 0;
   }
 
   if ( !rpcIsReq(pHead->msgType) ) {
     // for response, if code is auth failure, it shall bypass the auth process
     code = htonl(pHead->code);
-    if (code==TSDB_CODE_INVALID_TIME_STAMP || code==TSDB_CODE_AUTH_FAILURE || 
+    if (code==TSDB_CODE_INVALID_TIME_STAMP || code==TSDB_CODE_AUTH_FAILURE || code == TSDB_CODE_AUTH_REQUIRED || 
         code==TSDB_CODE_INVALID_USER || code == TSDB_CODE_NOT_READY) {
       pHead->msgLen = (int32_t)htonl((uint32_t)pHead->msgLen);
+      // tTrace("%s, dont check authentication since code is:0x%x", pConn->info, code);
       return 0;
     } 
   }
@@ -1388,12 +1403,12 @@ static int rpcCheckAuthentication(SRpcConn *pConn, char *msg, int msgLen) {
       } else {
         pHead->msgLen = (int32_t)htonl((uint32_t)pHead->msgLen) - sizeof(SRpcDigest);
         if ( !rpcIsReq(pHead->msgType) ) pConn->secured = 1;  // link is secured for client
-        //tTrace("%s, message is authenticated", pConn->info);
+        // tTrace("%s, message is authenticated", pConn->info);
       }
     }
   } else {
     tError("%s, auth spi:%d not matched with received:%d", pConn->info, pConn->spi, pHead->spi);
-    code = TSDB_CODE_AUTH_FAILURE;
+    code = pHead->spi ? TSDB_CODE_AUTH_FAILURE : TSDB_CODE_AUTH_REQUIRED;
   }
 
   return code;
diff --git a/src/util/src/ttimer.c b/src/util/src/ttimer.c
index 68db574d82f3e668ced4b8895c3427640641079e..55e7da3258c403934b7609fc71b05010070b41f4 100644
--- a/src/util/src/ttimer.c
+++ b/src/util/src/ttimer.c
@@ -342,6 +342,7 @@ static void taosTimerLoopFunc(int signo) {
   int64_t now = taosGetTimestampMs();
 
   for (int i = 0; i < tListLen(wheels); i++) {
+    tmrTrace("begin processing wheel %d", i);
     // `expried` is a temporary expire list.
     // expired timers are first add to this list, then move
     // to expired queue as a batch to improve performance.
@@ -389,6 +390,7 @@ static void taosTimerLoopFunc(int signo) {
     }
 
     addToExpired(expired);
+    tmrTrace("end processing wheel %d", i);
   }
 }