diff --git a/include/libs/transport/trpc.h b/include/libs/transport/trpc.h
index fdc9368b76..8dfd736df6 100644
--- a/include/libs/transport/trpc.h
+++ b/include/libs/transport/trpc.h
@@ -71,6 +71,10 @@ typedef struct SRpcInit {
   // call back to keep conn or not
   bool (*pfp)(void *parent, tmsg_t msgType);
 
+  // to support Send messages multiple times on a link  
+  // 
+  void* (*mfp)(void *parent, tmsg_t msgType);
+
   void *parent;
 } SRpcInit;
 
@@ -89,6 +93,9 @@ void    rpcSendRecv(void *shandle, SEpSet *pEpSet, SRpcMsg *pReq, SRpcMsg *pRsp)
 int     rpcReportProgress(void *pConn, char *pCont, int contLen);
 void    rpcCancelRequest(int64_t rid);
 
+// just release client conn to rpc instance, no close sock
+void rpcReleaseHandle(void *handle);   
+
 void rpcRefHandle(void *handle, int8_t type);
 void rpcUnrefHandle(void *handle, int8_t type);
 
diff --git a/source/libs/transport/inc/transComm.h b/source/libs/transport/inc/transComm.h
index f2ac77fe61..99f890d3a0 100644
--- a/source/libs/transport/inc/transComm.h
+++ b/source/libs/transport/inc/transComm.h
@@ -120,6 +120,10 @@ typedef struct {
   // SEpSet*          pSet;      // for synchronous API
 } SRpcReqContext;
 
+typedef SRpcMsg      STransMsg;
+typedef SRpcInfo     STrans;
+typedef SRpcConnInfo STransHandleInfo;
+
 typedef struct {
   SEpSet epSet;    // ip list provided by app
   void*  ahandle;  // handle provided by app
@@ -134,8 +138,8 @@ typedef struct {
   int8_t  connType;  // connection type
   int64_t rid;       // refId returned by taosAddRef
 
-  SRpcMsg* pRsp;  // for synchronous API
-  tsem_t*  pSem;  // for synchronous API
+  STransMsg* pRsp;  // for synchronous API
+  tsem_t*    pSem;  // for synchronous API
 
   int      hThrdIdx;
   char*    ip;
@@ -249,4 +253,15 @@ void transUnrefSrvHandle(void* handle);
 void transRefCliHandle(void* handle);
 void transUnrefCliHandle(void* handle);
 
+void transSendRequest(void* shandle, const char* ip, uint32_t port, STransMsg* pMsg);
+void transSendRecv(void* shandle, const char* ip, uint32_t port, STransMsg* pMsg, STransMsg* pRsp);
+void transSendResponse(const STransMsg* pMsg);
+int  transGetConnInfo(void* thandle, STransHandleInfo* pInfo);
+
+void* transInitServer(uint32_t ip, uint32_t port, char* label, int numOfThreads, void* fp, void* shandle);
+void* transInitClient(uint32_t ip, uint32_t port, char* label, int numOfThreads, void* fp, void* shandle);
+
+void transCloseClient(void* arg);
+void transCloseServer(void* arg);
+
 #endif
diff --git a/source/libs/transport/inc/transportInt.h b/source/libs/transport/inc/transportInt.h
index 4e4dcf7aa4..3924a5cf1a 100644
--- a/source/libs/transport/inc/transportInt.h
+++ b/source/libs/transport/inc/transportInt.h
@@ -64,6 +64,7 @@ typedef struct {
   void (*cfp)(void* parent, SRpcMsg*, SEpSet*);
   int (*afp)(void* parent, char* user, char* spi, char* encrypt, char* secret, char* ckey);
   bool (*pfp)(void* parent, tmsg_t msgType);
+  void* (*mfp)(void* parent, tmsg_t msgType);
 
   int32_t         refCount;
   void*           parent;
diff --git a/source/libs/transport/src/trans.c b/source/libs/transport/src/trans.c
index 4d244665c7..015018f73f 100644
--- a/source/libs/transport/src/trans.c
+++ b/source/libs/transport/src/trans.c
@@ -18,8 +18,9 @@
 #include "transComm.h"
 
 void* (*taosInitHandle[])(uint32_t ip, uint32_t port, char* label, int numOfThreads, void* fp, void* shandle) = {
-    taosInitServer, taosInitClient};
-void (*taosCloseHandle[])(void* arg) = {taosCloseServer, taosCloseClient};
+    transInitServer, transInitClient};
+
+void (*taosCloseHandle[])(void* arg) = {transCloseServer, transCloseClient};
 
 void* rpcOpen(const SRpcInit* pInit) {
   SRpcInfo* pRpc = calloc(1, sizeof(SRpcInfo));
@@ -34,11 +35,12 @@ void* rpcOpen(const SRpcInit* pInit) {
   pRpc->cfp = pInit->cfp;
   pRpc->afp = pInit->afp;
   pRpc->pfp = pInit->pfp;
+  pRpc->mfp = pInit->mfp;
 
   if (pInit->connType == TAOS_CONN_SERVER) {
     pRpc->numOfThreads = pInit->numOfThreads > TSDB_MAX_RPC_THREADS ? TSDB_MAX_RPC_THREADS : pInit->numOfThreads;
   } else {
-    pRpc->numOfThreads = pInit->numOfThreads;
+    pRpc->numOfThreads = pInit->numOfThreads > TSDB_MAX_RPC_THREADS ? TSDB_MAX_RPC_THREADS : pInit->numOfThreads;
   }
 
   pRpc->connType = pInit->connType;
@@ -116,6 +118,24 @@ int32_t rpcInit() {
   return 0;
 }
 
+void rpcSendRequest(void *shandle, const SEpSet *pEpSet, SRpcMsg* pMsg, int64_t *pRid) {
+  char*    ip = (char*)(pEpSet->eps[pEpSet->inUse].fqdn);
+  uint32_t port = pEpSet->eps[pEpSet->inUse].port;
+  transSendRequest(shandle, ip, port, pMsg);   
+}
+void rpcSendRecv(void* shandle, SEpSet *pEpSet, SRpcMsg *pMsg, SRpcMsg *pRsp) {
+  char*    ip = (char*)(pEpSet->eps[pEpSet->inUse].fqdn);
+  uint32_t port = pEpSet->eps[pEpSet->inUse].port;
+  transSendRecv(shandle, ip, port, pMsg, pRsp);
+}
+
+void rpcSendResponse(const SRpcMsg *pMsg) {
+  transSendResponse(pMsg);  
+}
+int rpcGetConnInfo(void *thandle, SRpcConnInfo *pInfo) {
+  return transGetConnInfo((void *)thandle, pInfo);
+}
+
 void rpcCleanup(void) {
   // impl later
   //
@@ -129,6 +149,7 @@ void rpcRefHandle(void* handle, int8_t type) {
   assert(type == TAOS_CONN_SERVER || type == TAOS_CONN_CLIENT);
   (*taosRefHandle[type])(handle);
 }
+
 void rpcUnrefHandle(void* handle, int8_t type) {
   assert(type == TAOS_CONN_SERVER || type == TAOS_CONN_CLIENT);
   (*taosUnRefHandle[type])(handle);
diff --git a/source/libs/transport/src/transCli.c b/source/libs/transport/src/transCli.c
index 727845b7a9..4af02a982e 100644
--- a/source/libs/transport/src/transCli.c
+++ b/source/libs/transport/src/transCli.c
@@ -42,7 +42,7 @@ typedef struct SCliConn {
 
 typedef struct SCliMsg {
   STransConnCtx* ctx;
-  SRpcMsg        msg;
+  STransMsg      msg;
   queue          q;
   uint64_t       st;
 } SCliMsg;
@@ -105,9 +105,9 @@ static void cliHandleExcept(SCliConn* conn);
 static void cliHandleReq(SCliMsg* pMsg, SCliThrdObj* pThrd);
 static void cliHandleQuit(SCliMsg* pMsg, SCliThrdObj* pThrd);
 static void cliSendQuit(SCliThrdObj* thrd);
-static void destroyUserdata(SRpcMsg* userdata);
+static void destroyUserdata(STransMsg* userdata);
 
-static int cliRBChoseIdx(SRpcInfo* pTransInst);
+static int cliRBChoseIdx(STrans* pTransInst);
 
 static void destroyCmsg(SCliMsg* cmsg);
 static void transDestroyConnCtx(STransConnCtx* ctx);
@@ -118,11 +118,11 @@ static void         destroyThrdObj(SCliThrdObj* pThrd);
 #define CONN_HOST_THREAD_INDEX(conn) (conn ? ((SCliConn*)conn)->hThrdIdx : -1)
 #define CONN_PERSIST_TIME(para) (para * 1000 * 10)
 
-#define CONN_GET_INST_LABEL(conn) (((SRpcInfo*)(((SCliThrdObj*)conn->hostThrd)->pTransInst))->label)
+#define CONN_GET_INST_LABEL(conn) (((STrans*)(((SCliThrdObj*)conn->hostThrd)->pTransInst))->label)
 #define CONN_HANDLE_THREAD_QUIT(conn, thrd) \
   do {                                      \
     if (thrd->quit) {                       \
-      cliHandleExcept(conn);             \
+      cliHandleExcept(conn);                \
       goto _RETURE;                         \
     }                                       \
   } while (0)
@@ -130,20 +130,25 @@ static void         destroyThrdObj(SCliThrdObj* pThrd);
 #define CONN_HANDLE_BROKEN(conn) \
   do {                           \
     if (conn->broken) {          \
-      cliHandleExcept(conn);  \
+      cliHandleExcept(conn);     \
       goto _RETURE;              \
     }                            \
   } while (0);
 
+#define CONN_SET_PERSIST_BY_APP(conn) \
+  do {                                \
+    if (conn->persist == false) {     \
+      conn->persist = true;           \
+      transRefCliHandle(conn);        \
+    }                                 \
+  } while (0)
+#define CONN_NO_PERSIST_BY_APP(conn) ((conn)->persist == false)
+
 static void* cliWorkThread(void* arg);
 
-static void* cliNotifyApp() {}
-static void  cliHandleResp(SCliConn* conn) {
-  SCliMsg*       pMsg = conn->data;
-  STransConnCtx* pCtx = pMsg->ctx;
-
+void cliHandleResp(SCliConn* conn) {
   SCliThrdObj* pThrd = conn->hostThrd;
-  SRpcInfo*    pTransInst = pThrd->pTransInst;
+  STrans*      pTransInst = pThrd->pTransInst;
 
   STransMsgHead* pHead = (STransMsgHead*)(conn->readBuf.buf);
   pHead->code = htonl(pHead->code);
@@ -152,19 +157,29 @@ static void  cliHandleResp(SCliConn* conn) {
   // buf's mem alread translated to rpcMsg.pCont
   transClearBuffer(&conn->readBuf);
 
-  SRpcMsg rpcMsg = {0};
+  STransMsg rpcMsg = {0};
   rpcMsg.contLen = transContLenFromMsg(pHead->msgLen);
   rpcMsg.pCont = transContFromHead((char*)pHead);
   rpcMsg.code = pHead->code;
   rpcMsg.msgType = pHead->msgType;
-  rpcMsg.ahandle = pCtx->ahandle;
+  rpcMsg.ahandle = NULL;
 
-  if (pTransInst->pfp != NULL && (pTransInst->pfp)(pTransInst->parent, rpcMsg.msgType)) {
+  SCliMsg*       pMsg = conn->data;
+  STransConnCtx* pCtx = pMsg ? pMsg->ctx : NULL;
+  if (pMsg == NULL && !CONN_NO_PERSIST_BY_APP(conn)) {
+    rpcMsg.ahandle = pTransInst->mfp ? (*pTransInst->mfp)(pTransInst->parent, rpcMsg.msgType) : NULL;
+  } else {
+    rpcMsg.ahandle = pCtx ? pCtx->ahandle : NULL;
+  }
+  // if (rpcMsg.ahandle == NULL) {
+  //  tDebug("%s cli conn %p handle except", CONN_GET_INST_LABEL(conn), conn);
+  //  return;
+  //}
+
+  if (pTransInst->pfp != NULL && (*pTransInst->pfp)(pTransInst->parent, rpcMsg.msgType)) {
     rpcMsg.handle = conn;
-    transRefCliHandle(conn);
-
-    conn->persist = 1;
-    tDebug("cli conn %p persist by app", conn);
+    CONN_SET_PERSIST_BY_APP(conn);
+    tDebug("%s cli conn %p ref by app", CONN_GET_INST_LABEL(conn), conn);
   }
 
   tDebug("%s cli conn %p %s received from %s:%d, local info: %s:%d, msg size: %d", pTransInst->label, conn,
@@ -173,7 +188,7 @@ static void  cliHandleResp(SCliConn* conn) {
 
   conn->secured = pHead->secured;
 
-  if (pCtx->pSem == NULL) {
+  if (pCtx == NULL || pCtx->pSem == NULL) {
     tTrace("%s cli conn %p handle resp", pTransInst->label, conn);
     (pTransInst->cfp)(pTransInst->parent, &rpcMsg, NULL);
   } else {
@@ -184,8 +199,7 @@ static void  cliHandleResp(SCliConn* conn) {
 
   uv_read_start((uv_stream_t*)conn->stream, cliAllocBufferCb, cliRecvCb);
 
-  // user owns conn->persist = 1
-  if (conn->persist == 0) {
+  if (CONN_NO_PERSIST_BY_APP(conn)) {
     addConnToPool(pThrd->pool, pCtx->ip, pCtx->port, conn);
   }
   destroyCmsg(conn->data);
@@ -196,24 +210,32 @@ static void  cliHandleResp(SCliConn* conn) {
     // uv_timer_start((uv_timer_t*)&pThrd->timer, cliTimeoutCb, CONN_PERSIST_TIME(pRpc->idleTime) / 2, 0);
   }
 }
-static void cliHandleExcept(SCliConn* pConn) {
+
+void cliHandleExcept(SCliConn* pConn) {
   if (pConn->data == NULL) {
-    // handle conn except in conn pool
-    transUnrefCliHandle(pConn);
-    return;
+    if (pConn->broken == true || CONN_NO_PERSIST_BY_APP(pConn)) {
+      transUnrefCliHandle(pConn);
+      return;
+    }
   }
   SCliThrdObj* pThrd = pConn->hostThrd;
-  SRpcInfo*    pTransInst = pThrd->pTransInst;
+  STrans*      pTransInst = pThrd->pTransInst;
 
   SCliMsg*       pMsg = pConn->data;
-  STransConnCtx* pCtx = pMsg->ctx;
+  STransConnCtx* pCtx = pMsg ? pMsg->ctx : NULL;
 
-  SRpcMsg rpcMsg = {0};
-  rpcMsg.ahandle = pCtx->ahandle;
+  STransMsg rpcMsg = {0};
   rpcMsg.code = TSDB_CODE_RPC_NETWORK_UNAVAIL;
-  rpcMsg.msgType = pMsg->msg.msgType + 1;
+  rpcMsg.msgType = pMsg ? pMsg->msg.msgType + 1 : 0;
+  rpcMsg.ahandle = NULL;
 
-  if (pCtx->pSem == NULL) {
+  if (pMsg == NULL && !CONN_NO_PERSIST_BY_APP(pConn)) {
+    rpcMsg.ahandle = pTransInst->mfp ? (*pTransInst->mfp)(pTransInst->parent, rpcMsg.msgType) : NULL;
+  } else {
+    rpcMsg.ahandle = pCtx ? pCtx->ahandle : NULL;
+  }
+
+  if (pCtx == NULL || pCtx->pSem == NULL) {
     tTrace("%s cli conn %p handle resp", pTransInst->label, pConn);
     (pTransInst->cfp)(pTransInst->parent, &rpcMsg, NULL);
   } else {
@@ -228,9 +250,9 @@ static void cliHandleExcept(SCliConn* pConn) {
   transUnrefCliHandle(pConn);
 }
 
-static void cliTimeoutCb(uv_timer_t* handle) {
+void cliTimeoutCb(uv_timer_t* handle) {
   SCliThrdObj* pThrd = handle->data;
-  SRpcInfo*    pRpc = pThrd->pTransInst;
+  STrans*      pRpc = pThrd->pTransInst;
   int64_t      currentTime = pThrd->nextTimeout;
   tTrace("%s, cli conn timeout, try to remove expire conn from conn pool", pRpc->label);
 
@@ -252,11 +274,12 @@ static void cliTimeoutCb(uv_timer_t* handle) {
   pThrd->nextTimeout = taosGetTimestampMs() + CONN_PERSIST_TIME(pRpc->idleTime);
   uv_timer_start(handle, cliTimeoutCb, CONN_PERSIST_TIME(pRpc->idleTime) / 2, 0);
 }
-static void* createConnPool(int size) {
+
+void* createConnPool(int size) {
   // thread local, no lock
   return taosHashInit(size, taosGetDefaultHashFunction(TSDB_DATA_TYPE_BINARY), false, HASH_NO_LOCK);
 }
-static void* destroyConnPool(void* pool) {
+void* destroyConnPool(void* pool) {
   SConnList* connList = taosHashIterate((SHashObj*)pool, NULL);
   while (connList != NULL) {
     while (!QUEUE_IS_EMPTY(&connList->conn)) {
@@ -301,7 +324,7 @@ static void addConnToPool(void* pool, char* ip, uint32_t port, SCliConn* conn) {
   tstrncpy(key + strlen(key), (char*)(&port), sizeof(port));
   tTrace("cli conn %p added to conn pool, read buf cap: %d", conn, conn->readBuf.cap);
 
-  SRpcInfo* pRpc = ((SCliThrdObj*)conn->hostThrd)->pTransInst;
+  STrans* pRpc = ((SCliThrdObj*)conn->hostThrd)->pTransInst;
 
   conn->expireTime = taosGetTimestampMs() + CONN_PERSIST_TIME(pRpc->idleTime);
   SConnList* plist = taosHashGet((SHashObj*)pool, key, strlen(key));
@@ -358,6 +381,7 @@ static SCliConn* cliCreateConn(SCliThrdObj* pThrd) {
 
   QUEUE_INIT(&conn->conn);
   conn->hostThrd = pThrd;
+  conn->persist = false;
   conn->broken = false;
   transRefCliHandle(conn);
   return conn;
@@ -395,16 +419,16 @@ static void cliSendCb(uv_write_t* req, int status) {
   uv_read_start((uv_stream_t*)pConn->stream, cliAllocBufferCb, cliRecvCb);
 }
 
-static void cliSend(SCliConn* pConn) {
+void cliSend(SCliConn* pConn) {
   CONN_HANDLE_BROKEN(pConn);
 
   SCliMsg*       pCliMsg = pConn->data;
   STransConnCtx* pCtx = pCliMsg->ctx;
 
   SCliThrdObj* pThrd = pConn->hostThrd;
-  SRpcInfo*    pTransInst = pThrd->pTransInst;
+  STrans*      pTransInst = pThrd->pTransInst;
 
-  SRpcMsg* pMsg = (SRpcMsg*)(&pCliMsg->msg);
+  STransMsg* pMsg = (STransMsg*)(&pCliMsg->msg);
 
   STransMsgHead* pHead = transHeadFromCont(pMsg->pCont);
   int            msgLen = transMsgLenFromCont(pMsg->contLen);
@@ -442,7 +466,8 @@ static void cliSend(SCliConn* pConn) {
 _RETURE:
   return;
 }
-static void cliConnCb(uv_connect_t* req, int status) {
+
+void cliConnCb(uv_connect_t* req, int status) {
   // impl later
   SCliConn* pConn = req->data;
   if (status != 0) {
@@ -472,11 +497,11 @@ static void cliHandleQuit(SCliMsg* pMsg, SCliThrdObj* pThrd) {
   pThrd->quit = true;
   uv_stop(pThrd->loop);
 }
-static SCliConn* cliGetConn(SCliMsg* pMsg, SCliThrdObj* pThrd) {
+
+SCliConn* cliGetConn(SCliMsg* pMsg, SCliThrdObj* pThrd) {
   SCliConn* conn = NULL;
   if (pMsg->msg.handle != NULL) {
     conn = (SCliConn*)(pMsg->msg.handle);
-    transUnrefCliHandle(conn);
     if (conn != NULL) {
       tTrace("%s cli conn %p reused", CONN_GET_INST_LABEL(conn), conn);
     }
@@ -487,13 +512,14 @@ static SCliConn* cliGetConn(SCliMsg* pMsg, SCliThrdObj* pThrd) {
   }
   return conn;
 }
-static void cliHandleReq(SCliMsg* pMsg, SCliThrdObj* pThrd) {
+
+void cliHandleReq(SCliMsg* pMsg, SCliThrdObj* pThrd) {
   uint64_t et = taosGetTimestampUs();
   uint64_t el = et - pMsg->st;
-  tTrace("%s cli msg tran time cost: %" PRIu64 "us", ((SRpcInfo*)pThrd->pTransInst)->label, el);
+  tTrace("%s cli msg tran time cost: %" PRIu64 "us", ((STrans*)pThrd->pTransInst)->label, el);
 
   STransConnCtx* pCtx = pMsg->ctx;
-  SRpcInfo*      pTransInst = pThrd->pTransInst;
+  STrans*        pTransInst = pThrd->pTransInst;
 
   SCliConn* conn = cliGetConn(pMsg, pThrd);
   if (conn != NULL) {
@@ -514,6 +540,7 @@ static void cliHandleReq(SCliMsg* pMsg, SCliThrdObj* pThrd) {
     tTrace("%s cli conn %p try to connect to %s:%d", pTransInst->label, conn, pMsg->ctx->ip, pMsg->ctx->port);
     uv_tcp_connect(&conn->connReq, (uv_tcp_t*)(conn->stream), (const struct sockaddr*)&addr, cliConnCb);
   }
+
   conn->hThrdIdx = pCtx->hThrdIdx;
 }
 static void cliAsyncCb(uv_async_t* handle) {
@@ -522,7 +549,7 @@ static void cliAsyncCb(uv_async_t* handle) {
   SCliMsg*     pMsg = NULL;
 
   // batch process to avoid to lock/unlock frequently
-  queue        wq;
+  queue wq;
   pthread_mutex_lock(&item->mtx);
   QUEUE_MOVE(&item->qmsg, &wq);
   pthread_mutex_unlock(&item->mtx);
@@ -551,10 +578,10 @@ static void* cliWorkThread(void* arg) {
   uv_run(pThrd->loop, UV_RUN_DEFAULT);
 }
 
-void* taosInitClient(uint32_t ip, uint32_t port, char* label, int numOfThreads, void* fp, void* shandle) {
+void* transInitClient(uint32_t ip, uint32_t port, char* label, int numOfThreads, void* fp, void* shandle) {
   SCliObj* cli = calloc(1, sizeof(SCliObj));
 
-  SRpcInfo* pRpc = shandle;
+  STrans* pRpc = shandle;
   memcpy(cli->label, label, strlen(label));
   cli->numOfThreads = numOfThreads;
   cli->pThreadObj = (SCliThrdObj**)calloc(cli->numOfThreads, sizeof(SCliThrdObj*));
@@ -573,7 +600,7 @@ void* taosInitClient(uint32_t ip, uint32_t port, char* label, int numOfThreads,
   return cli;
 }
 
-static void destroyUserdata(SRpcMsg* userdata) {
+static void destroyUserdata(STransMsg* userdata) {
   if (userdata->pCont == NULL) {
     return;
   }
@@ -629,12 +656,20 @@ static void transDestroyConnCtx(STransConnCtx* ctx) {
   free(ctx);
 }
 //
-static void cliSendQuit(SCliThrdObj* thrd) {
+void cliSendQuit(SCliThrdObj* thrd) {
   // cli can stop gracefully
   SCliMsg* msg = calloc(1, sizeof(SCliMsg));
   transSendAsync(thrd->asyncPool, &msg->q);
 }
-void taosCloseClient(void* arg) {
+int cliRBChoseIdx(STrans* pTransInst) {
+  int64_t index = pTransInst->index;
+  if (pTransInst->index++ >= pTransInst->numOfThreads) {
+    pTransInst->index = 0;
+  }
+  return index % pTransInst->numOfThreads;
+}
+
+void transCloseClient(void* arg) {
   SCliObj* cli = arg;
   for (int i = 0; i < cli->numOfThreads; i++) {
     cliSendQuit(cli->pThreadObj[i]);
@@ -643,13 +678,6 @@ void taosCloseClient(void* arg) {
   free(cli->pThreadObj);
   free(cli);
 }
-static int cliRBChoseIdx(SRpcInfo* pTransInst) {
-  int64_t index = pTransInst->index;
-  if (pTransInst->index++ >= pTransInst->numOfThreads) {
-    pTransInst->index = 0;
-  }
-  return index % pTransInst->numOfThreads;
-}
 void transRefCliHandle(void* handle) {
   if (handle == NULL) {
     return;
@@ -665,17 +693,11 @@ void transUnrefCliHandle(void* handle) {
   if (ref == 0) {
     cliDestroyConn((SCliConn*)handle, true);
   }
-
-  // unref cli handle
 }
-void rpcSendRequest(void* shandle, const SEpSet* pEpSet, SRpcMsg* pMsg, int64_t* pRid) {
-  // impl later
-  char*    ip = (char*)(pEpSet->eps[pEpSet->inUse].fqdn);
-  uint32_t port = pEpSet->eps[pEpSet->inUse].port;
 
-  SRpcInfo* pTransInst = (SRpcInfo*)shandle;
-
-  int index = CONN_HOST_THREAD_INDEX(pMsg->handle);
+void transSendRequest(void* shandle, const char* ip, uint32_t port, STransMsg* pMsg) {
+  STrans* pTransInst = (STrans*)shandle;
+  int     index = CONN_HOST_THREAD_INDEX((SCliConn*)pMsg->handle);
   if (index == -1) {
     index = cliRBChoseIdx(pTransInst);
   }
@@ -683,6 +705,7 @@ void rpcSendRequest(void* shandle, const SEpSet* pEpSet, SRpcMsg* pMsg, int64_t*
   if (transCompressMsg(pMsg->pCont, pMsg->contLen, &flen)) {
     // imp later
   }
+  tDebug("send request at thread:%d %p", index, pMsg);
   STransConnCtx* pCtx = calloc(1, sizeof(STransConnCtx));
   pCtx->ahandle = pMsg->ahandle;
   pCtx->msgType = pMsg->msgType;
@@ -701,14 +724,9 @@ void rpcSendRequest(void* shandle, const SEpSet* pEpSet, SRpcMsg* pMsg, int64_t*
   SCliThrdObj* thrd = ((SCliObj*)pTransInst->tcphandle)->pThreadObj[index];
   transSendAsync(thrd->asyncPool, &(cliMsg->q));
 }
-
-void rpcSendRecv(void* shandle, SEpSet* pEpSet, SRpcMsg* pReq, SRpcMsg* pRsp) {
-  char*    ip = (char*)(pEpSet->eps[pEpSet->inUse].fqdn);
-  uint32_t port = pEpSet->eps[pEpSet->inUse].port;
-
-  SRpcInfo* pTransInst = (SRpcInfo*)shandle;
-
-  int index = CONN_HOST_THREAD_INDEX(pReq->handle);
+void transSendRecv(void* shandle, const char* ip, uint32_t port, STransMsg* pReq, STransMsg* pRsp) {
+  STrans* pTransInst = (STrans*)shandle;
+  int     index = CONN_HOST_THREAD_INDEX(pReq->handle);
   if (index == -1) {
     index = cliRBChoseIdx(pTransInst);
   }
@@ -734,7 +752,6 @@ void rpcSendRecv(void* shandle, SEpSet* pEpSet, SRpcMsg* pReq, SRpcMsg* pRsp) {
   tsem_wait(pSem);
   tsem_destroy(pSem);
   free(pSem);
-
-  return;
 }
+
 #endif
diff --git a/source/libs/transport/src/transSrv.c b/source/libs/transport/src/transSrv.c
index 1abca9ad97..c236a69f4e 100644
--- a/source/libs/transport/src/transSrv.c
+++ b/source/libs/transport/src/transSrv.c
@@ -37,8 +37,7 @@ typedef struct SSrvConn {
 
   struct sockaddr_in addr;
   struct sockaddr_in locaddr;
-  // SRpcMsg sendMsg;
-  // del later
+
   char secured;
   int  spi;
   char info[64];
@@ -49,7 +48,7 @@ typedef struct SSrvConn {
 
 typedef struct SSrvMsg {
   SSrvConn* pConn;
-  SRpcMsg   msg;
+  STransMsg msg;
   queue     q;
 } SSrvMsg;
 
@@ -207,20 +206,20 @@ static void uvHandleReq(SSrvConn* pConn) {
 
   pConn->inType = pHead->msgType;
 
-  SRpcInfo* pRpc = (SRpcInfo*)p->shandle;
+  STrans* pRpc = (STrans*)p->shandle;
   pHead->code = htonl(pHead->code);
 
   int32_t dlen = 0;
   if (transDecompressMsg(NULL, 0, NULL)) {
     // add compress later
-    // pHead = rpcDecompressRpcMsg(pHead);
+    // pHead = rpcDecompresSTransMsg(pHead);
   } else {
     pHead->msgLen = htonl(pHead->msgLen);
     // impl later
     //
   }
 
-  SRpcMsg rpcMsg;
+  STransMsg rpcMsg;
   rpcMsg.contLen = transContLenFromMsg(pHead->msgLen);
   rpcMsg.pCont = pHead->content;
   rpcMsg.msgType = pHead->msgType;
@@ -260,7 +259,7 @@ void uvOnRecvCb(uv_stream_t* cli, ssize_t nread, const uv_buf_t* buf) {
   }
 
   tError("server conn %p read error: %s", conn, uv_err_name(nread));
-  if (nread < 0 || nread == UV_EOF) {
+  if (nread < 0) {
     conn->broken = true;
     transUnrefSrvHandle(conn);
 
@@ -318,8 +317,8 @@ static void uvPrepareSendData(SSrvMsg* smsg, uv_buf_t* wb) {
   // impl later;
   tTrace("server conn %p prepare to send resp", smsg->pConn);
 
-  SSrvConn* pConn = smsg->pConn;
-  SRpcMsg*  pMsg = &smsg->msg;
+  SSrvConn*  pConn = smsg->pConn;
+  STransMsg* pMsg = &smsg->msg;
   if (pMsg->pCont == 0) {
     pMsg->pCont = (void*)rpcMallocCont(0);
     pMsg->contLen = 0;
@@ -547,7 +546,7 @@ static bool addHandleToWorkloop(void* arg) {
     return false;
   }
 
-  // SRpcInfo* pRpc = pThrd->shandle;
+  // STrans* pRpc = pThrd->shandle;
   uv_pipe_init(pThrd->loop, pThrd->pipe, 1);
   uv_pipe_open(pThrd->pipe, pThrd->fd);
 
@@ -668,7 +667,7 @@ static int transAddAuthPart(SSrvConn* pConn, char* msg, int msgLen) {
   return msgLen;
 }
 
-void* taosInitServer(uint32_t ip, uint32_t port, char* label, int numOfThreads, void* fp, void* shandle) {
+void* transInitServer(uint32_t ip, uint32_t port, char* label, int numOfThreads, void* fp, void* shandle) {
   SServerObj* srv = calloc(1, sizeof(SServerObj));
   srv->loop = (uv_loop_t*)malloc(sizeof(uv_loop_t));
   srv->numOfThreads = numOfThreads;
@@ -720,7 +719,7 @@ void* taosInitServer(uint32_t ip, uint32_t port, char* label, int numOfThreads,
 
   return srv;
 End:
-  taosCloseServer(srv);
+  transCloseServer(srv);
   return NULL;
 }
 
@@ -740,7 +739,7 @@ void sendQuitToWorkThrd(SWorkThrdObj* pThrd) {
   transSendAsync(pThrd->asyncPool, &srvMsg->q);
 }
 
-void taosCloseServer(void* arg) {
+void transCloseServer(void* arg) {
   // impl later
   SServerObj* srv = arg;
   for (int i = 0; i < srv->numOfThreads; i++) {
@@ -786,7 +785,7 @@ void transUnrefSrvHandle(void* handle) {
   }
   // unref srv handle
 }
-void rpcSendResponse(const SRpcMsg* pMsg) {
+void transSendResponse(const STransMsg* pMsg) {
   if (pMsg->handle == NULL) {
     return;
   }
@@ -799,14 +798,12 @@ void rpcSendResponse(const SRpcMsg* pMsg) {
   tTrace("server conn %p start to send resp", pConn);
   transSendAsync(pThrd->asyncPool, &srvMsg->q);
 }
-
-int rpcGetConnInfo(void* thandle, SRpcConnInfo* pInfo) {
-  SSrvConn* pConn = thandle;
-
+int transGetConnInfo(void* thandle, STransHandleInfo* pInfo) {
+  SSrvConn*          pConn = thandle;
   struct sockaddr_in addr = pConn->addr;
+
   pInfo->clientIp = (uint32_t)(addr.sin_addr.s_addr);
   pInfo->clientPort = ntohs(addr.sin_port);
-
   tstrncpy(pInfo->user, pConn->user, sizeof(pInfo->user));
   return 0;
 }