diff --git a/src/client/src/tscSystem.c b/src/client/src/tscSystem.c
index d3c8eefbb9..fd7d31aa9f 100644
--- a/src/client/src/tscSystem.c
+++ b/src/client/src/tscSystem.c
@@ -201,7 +201,7 @@ static int taos_options_imp(TSDB_OPTION option, const char *pStr) {
         tscPrint("set shellActivityTimer:%d", tsShellActivityTimer);
       } else {
         tscWarn("config option:%s, input value:%s, is configured by %s, use %d", cfg->option, pStr,
-                tsCfgStatusStr[cfg->cfgStatus], (int32_t *)cfg->ptr);
+                tsCfgStatusStr[cfg->cfgStatus], *(int32_t *)cfg->ptr);
       }
       break;
 
diff --git a/src/connector/python/linux/python2/taos/cursor.py b/src/connector/python/linux/python2/taos/cursor.py
index f7c840442e..8c268d8afb 100644
--- a/src/connector/python/linux/python2/taos/cursor.py
+++ b/src/connector/python/linux/python2/taos/cursor.py
@@ -137,7 +137,7 @@ class TDengineCursor(object):
         else:
             raise ProgrammingError(
                 CTaosInterface.errStr(
-                    self._result ))
+                    self._result ), errno)
 
     def executemany(self, operation, seq_of_parameters):
         """Prepare a database operation (query or command) and then execute it against all parameter sequences or mappings found in the sequence seq_of_parameters.
diff --git a/src/connector/python/linux/python3/taos/cursor.py b/src/connector/python/linux/python3/taos/cursor.py
index 5db5365eb3..06d6a19462 100644
--- a/src/connector/python/linux/python3/taos/cursor.py
+++ b/src/connector/python/linux/python3/taos/cursor.py
@@ -139,7 +139,7 @@ class TDengineCursor(object):
         else:
             raise ProgrammingError(
                 CTaosInterface.errStr(
-                    self._result ))
+                    self._result), errno)
 
     def executemany(self, operation, seq_of_parameters):
         """Prepare a database operation (query or command) and then execute it against all parameter sequences or mappings found in the sequence seq_of_parameters.
diff --git a/src/connector/python/windows/python2/taos/cursor.py b/src/connector/python/windows/python2/taos/cursor.py
index 1da726638a..7eee3bfc8f 100644
--- a/src/connector/python/windows/python2/taos/cursor.py
+++ b/src/connector/python/windows/python2/taos/cursor.py
@@ -117,7 +117,7 @@ class TDengineCursor(object):
                 self._fields = CTaosInterface.useResult(self._result)
                 return self._handle_result()
         else:
-            raise ProgrammingError(CTaosInterface.errStr(self._result))
+            raise ProgrammingError(CTaosInterface.errStr(self._result), errno)
 
     def executemany(self, operation, seq_of_parameters):
         """Prepare a database operation (query or command) and then execute it against all parameter sequences or mappings found in the sequence seq_of_parameters.
diff --git a/src/connector/python/windows/python3/taos/cursor.py b/src/connector/python/windows/python3/taos/cursor.py
index 2dcd0aaccb..5f5aa4e1d7 100644
--- a/src/connector/python/windows/python3/taos/cursor.py
+++ b/src/connector/python/windows/python3/taos/cursor.py
@@ -117,7 +117,7 @@ class TDengineCursor(object):
                 self._fields = CTaosInterface.useResult(self._result )
                 return self._handle_result()
         else:
-            raise ProgrammingError(CTaosInterface.errStr(self._result ))
+            raise ProgrammingError(CTaosInterface.errStr(self._result ), errno)
 
     def executemany(self, operation, seq_of_parameters):
         """Prepare a database operation (query or command) and then execute it against all parameter sequences or mappings found in the sequence seq_of_parameters.
diff --git a/src/dnode/src/dnodeSystem.c b/src/dnode/src/dnodeSystem.c
index 97cf6f7eeb..0a983362c2 100644
--- a/src/dnode/src/dnodeSystem.c
+++ b/src/dnode/src/dnodeSystem.c
@@ -92,6 +92,7 @@ int32_t main(int32_t argc, char *argv[]) {
   // Initialize the system
   if (dnodeInitSystem() < 0) {
     syslog(LOG_ERR, "Error initialize TDengine system");
+    dPrint("Failed to start TDengine, please check the log at:%s", tsLogDir);
     closelog();
     exit(EXIT_FAILURE);
   }
diff --git a/src/os/linux/src/linuxSysPara.c b/src/os/linux/src/linuxSysPara.c
index ca244dcd94..b270eb14cf 100644
--- a/src/os/linux/src/linuxSysPara.c
+++ b/src/os/linux/src/linuxSysPara.c
@@ -331,66 +331,7 @@ bool taosGetDisk() {
   return true;
 }
 
-static bool taosGetCardName(char *ip, char *name) {
-  struct ifaddrs *ifaddr, *ifa;
-  int             family, s;
-  char            host[NI_MAXHOST];
-  bool            ret = false;
-
-  if (getifaddrs(&ifaddr) == -1) {
-    return false;
-  }
-
-  /* Walk through linked list, maintaining head pointer so we can free list
-   * later */
-  for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
-    if (ifa->ifa_addr == NULL) continue;
-
-    family = ifa->ifa_addr->sa_family;
-    if (family != AF_INET) {
-      continue;
-    }
-
-    s = getnameinfo(ifa->ifa_addr, (family == AF_INET) ? sizeof(struct sockaddr_in) : sizeof(struct sockaddr_in6), host,
-                    NI_MAXHOST, NULL, 0, NI_NUMERICHOST);
-    if (s != 0) {
-      break;
-    }
-
-    if (strcmp(host, "127.0.0.1") == 0) {
-      continue;
-    }
-
-    // TODO: the ip not config
-    // if (strcmp(host, ip) == 0) {
-    strcpy(name, ifa->ifa_name);
-    ret = true;
-    // }
-  }
-
-  freeifaddrs(ifaddr);
-  return ret;
-}
-
 static bool taosGetCardInfo(int64_t *bytes) {
-  static char tsPublicCard[1000] = {0};
-  static char tsPrivateIp[40];
-
-  if (tsPublicCard[0] == 0) {
-    if (!taosGetCardName(tsPrivateIp, tsPublicCard)) {
-      uError("can't get card name from ip:%s", tsPrivateIp);
-      return false;
-    }
-    int cardNameLen = (int)strlen(tsPublicCard);
-    for (int i = 0; i < cardNameLen; ++i) {
-      if (tsPublicCard[i] == ':') {
-        tsPublicCard[i] = 0;
-        break;
-      }
-    }
-    // uTrace("card name of public ip:%s is %s", tsPublicIp, tsPublicCard);
-  }
-
   FILE *fp = fopen(tsSysNetFile, "r");
   if (fp == NULL) {
     uError("open file:%s failed", tsSysNetFile);
@@ -403,6 +344,7 @@ static bool taosGetCardInfo(int64_t *bytes) {
 
   size_t len;
   char * line = NULL;
+  *bytes = 0;
 
   while (!feof(fp)) {
     tfree(line);
@@ -411,23 +353,20 @@ static bool taosGetCardInfo(int64_t *bytes) {
     if (line == NULL) {
       break;
     }
-    if (strstr(line, tsPublicCard) != NULL) {
-      break;
+    if (strstr(line, "lo:") != NULL) {
+      continue;
     }
+
+    sscanf(line,
+           "%s %" PRId64 " %" PRId64 " %" PRId64 " %" PRId64 " %" PRId64 " %" PRId64 " %" PRId64 " %" PRId64 " %" PRId64 " %" PRId64,
+           nouse0, &rbytes, &rpackts, &nouse1, &nouse2, &nouse3, &nouse4, &nouse5, &nouse6, &tbytes, &tpackets);
+    *bytes += (rbytes + tbytes);
   }
-  if (line != NULL) {
-    sscanf(line, "%s %" PRId64 " %" PRId64 " %" PRId64 " %" PRId64 " %" PRId64 " %" PRId64 " %" PRId64 " %" PRId64 " %" PRId64 " %" PRId64, nouse0, &rbytes, &rpackts, &nouse1, &nouse2, &nouse3,
-           &nouse4, &nouse5, &nouse6, &tbytes, &tpackets);
-    *bytes = rbytes + tbytes;
-    tfree(line);
-    fclose(fp);
-    return true;
-  } else {
-    uWarn("can't get card:%s info from device:%s", tsPublicCard, tsSysNetFile);
-    *bytes = 0;
-    fclose(fp);
-    return false;
-  }
+
+  tfree(line);
+  fclose(fp);
+
+  return true;
 }
 
 bool taosGetBandSpeed(float *bandSpeedKb) {
@@ -443,13 +382,15 @@ bool taosGetBandSpeed(float *bandSpeedKb) {
   if (lastTime == 0 || lastBytes == 0) {
     lastTime = curTime;
     lastBytes = curBytes;
-    return false;
+    *bandSpeedKb = 0;
+    return true;
   }
 
   if (lastTime >= curTime || lastBytes > curBytes) {
     lastTime = curTime;
     lastBytes = curBytes;
-    return false;
+    *bandSpeedKb = 0;
+    return true;
   }
 
   double totalBytes = (double)(curBytes - lastBytes) / 1024 * 8;  // Kb
diff --git a/src/rpc/src/rpcTcp.c b/src/rpc/src/rpcTcp.c
index 04a269502e..7035b30b66 100644
--- a/src/rpc/src/rpcTcp.c
+++ b/src/rpc/src/rpcTcp.c
@@ -67,7 +67,7 @@ static void   *taosProcessTcpData(void *param);
 static SFdObj *taosMallocFdObj(SThreadObj *pThreadObj, int fd);
 static void    taosFreeFdObj(SFdObj *pFdObj);
 static void    taosReportBrokenLink(SFdObj *pFdObj);
-static void*   taosAcceptTcpConnection(void *arg);
+static void   *taosAcceptTcpConnection(void *arg);
 
 void *taosInitTcpServer(uint32_t ip, uint16_t port, char *label, int numOfThreads, void *fp, void *shandle) {
   SServerObj *pServerObj;
@@ -80,6 +80,7 @@ void *taosInitTcpServer(uint32_t ip, uint16_t port, char *label, int numOfThread
     return NULL;
   }
 
+  pServerObj->fd = -1;
   pServerObj->thread = 0;
   pServerObj->ip = ip;
   pServerObj->port = port;
@@ -99,6 +100,7 @@ void *taosInitTcpServer(uint32_t ip, uint16_t port, char *label, int numOfThread
   pthread_attr_init(&thattr);
   pthread_attr_setdetachstate(&thattr, PTHREAD_CREATE_JOINABLE);
 
+  // initialize parameters in case it may encounter error later 
   pThreadObj = pServerObj->pThreadObj;
   for (int i = 0; i < numOfThreads; ++i) {
     pThreadObj->pollFd = -1;
@@ -106,18 +108,21 @@ void *taosInitTcpServer(uint32_t ip, uint16_t port, char *label, int numOfThread
     pThreadObj->processData = fp;
     tstrncpy(pThreadObj->label, label, sizeof(pThreadObj->label));
     pThreadObj->shandle = shandle;
+    pThreadObj++;
+  }
 
+  // initialize mutex, thread, fd which may fail
+  pThreadObj = pServerObj->pThreadObj;
+  for (int i = 0; i < numOfThreads; ++i) {
     code = pthread_mutex_init(&(pThreadObj->mutex), NULL);
     if (code < 0) {
       tError("%s failed to init TCP process data mutex(%s)", label, strerror(errno));
-      terrno = TAOS_SYSTEM_ERROR(errno); 
       break;;
     }
 
     pThreadObj->pollFd = epoll_create(10);  // size does not matter
     if (pThreadObj->pollFd < 0) {
       tError("%s failed to create TCP epoll", label);
-      terrno = TAOS_SYSTEM_ERROR(errno); 
       code = -1;
       break;
     }
@@ -125,7 +130,6 @@ void *taosInitTcpServer(uint32_t ip, uint16_t port, char *label, int numOfThread
     code = pthread_create(&(pThreadObj->thread), &thattr, taosProcessTcpData, (void *)(pThreadObj));
     if (code != 0) {
       tError("%s failed to create TCP process data thread(%s)", label, strerror(errno));
-      terrno = TAOS_SYSTEM_ERROR(errno); 
       break;
     }
 
@@ -133,15 +137,18 @@ void *taosInitTcpServer(uint32_t ip, uint16_t port, char *label, int numOfThread
     pThreadObj++;
   }
 
+  pServerObj->fd = taosOpenTcpServerSocket(pServerObj->ip, pServerObj->port);
+  if (pServerObj->fd < 0) code = -1; 
+
   if (code == 0) { 
-    code = pthread_create(&(pServerObj->thread), &thattr, (void *)taosAcceptTcpConnection, (void *)(pServerObj));
+    code = pthread_create(&pServerObj->thread, &thattr, taosAcceptTcpConnection, (void *)pServerObj);
     if (code != 0) {
-      terrno = TAOS_SYSTEM_ERROR(errno); 
       tError("%s failed to create TCP accept thread(%s)", label, strerror(errno));
     }
   }
 
   if (code != 0) {
+    terrno = TAOS_SYSTEM_ERROR(errno); 
     taosCleanUpTcpServer(pServerObj);
     pServerObj = NULL;
   } else {
@@ -204,7 +211,7 @@ void taosCleanUpTcpServer(void *handle) {
   tfree(pServerObj);
 }
 
-static void* taosAcceptTcpConnection(void *arg) {
+static void *taosAcceptTcpConnection(void *arg) {
   int                connFd = -1;
   struct sockaddr_in caddr;
   int                threadId = 0;
@@ -212,10 +219,6 @@ static void* taosAcceptTcpConnection(void *arg) {
   SServerObj        *pServerObj;
 
   pServerObj = (SServerObj *)arg;
-
-  pServerObj->fd = taosOpenTcpServerSocket(pServerObj->ip, pServerObj->port);
-  if (pServerObj->fd < 0) return NULL; 
-
   tTrace("%s TCP server is ready, ip:0x%x:%hu", pServerObj->label, pServerObj->ip, pServerObj->port);
 
   while (1) {
diff --git a/src/rpc/src/rpcUdp.c b/src/rpc/src/rpcUdp.c
index 7e2fe0db61..279cf7ed49 100644
--- a/src/rpc/src/rpcUdp.c
+++ b/src/rpc/src/rpcUdp.c
@@ -19,6 +19,7 @@
 #include "ttimer.h"
 #include "tutil.h"
 #include "taosdef.h"
+#include "taoserror.h"
 #include "rpcLog.h"
 #include "rpcUdp.h"
 #include "rpcHead.h"
@@ -65,6 +66,7 @@ void *taosInitUdpConnection(uint32_t ip, uint16_t port, char *label, int threads
   pSet = (SUdpConnSet *)malloc((size_t)size);
   if (pSet == NULL) {
     tError("%s failed to allocate UdpConn", label);
+    terrno = TAOS_SYSTEM_ERROR(errno);
     return NULL;
   }
 
@@ -73,30 +75,34 @@ void *taosInitUdpConnection(uint32_t ip, uint16_t port, char *label, int threads
   pSet->port = port;
   pSet->shandle = shandle;
   pSet->fp = fp;
+  pSet->threads = threads;
   tstrncpy(pSet->label, label, sizeof(pSet->label));
 
+  pthread_attr_t thAttr;
+  pthread_attr_init(&thAttr);
+  pthread_attr_setdetachstate(&thAttr, PTHREAD_CREATE_JOINABLE);
+
+  int i;
   uint16_t ownPort;
-  for (int i = 0; i < threads; ++i) {
+  for (i = 0; i < threads; ++i) {
     pConn = pSet->udpConn + i;
     ownPort = (port ? port + i : 0);
     pConn->fd = taosOpenUdpSocket(ip, ownPort);
     if (pConn->fd < 0) {
       tError("%s failed to open UDP socket %x:%hu", label, ip, port);
-      taosCleanUpUdpConnection(pSet);
-      return NULL;
+      break;
     }
 
     pConn->buffer = malloc(RPC_MAX_UDP_SIZE);
     if (NULL == pConn->buffer) {
       tError("%s failed to malloc recv buffer", label);
-      taosCleanUpUdpConnection(pSet);
-      return NULL;
+      break;
     }
 
     struct sockaddr_in sin;
     unsigned int addrlen = sizeof(sin);
-    if (getsockname(pConn->fd, (struct sockaddr *)&sin, &addrlen) == 0 && sin.sin_family == AF_INET &&
-        addrlen == sizeof(sin)) {
+    if (getsockname(pConn->fd, (struct sockaddr *)&sin, &addrlen) == 0 && 
+        sin.sin_family == AF_INET && addrlen == sizeof(sin)) {
       pConn->localPort = (uint16_t)ntohs(sin.sin_port);
     }
 
@@ -107,23 +113,22 @@ void *taosInitUdpConnection(uint32_t ip, uint16_t port, char *label, int threads
     pConn->pSet = pSet;
     pConn->signature = pConn;
 
-    pthread_attr_t thAttr;
-    pthread_attr_init(&thAttr);
-    pthread_attr_setdetachstate(&thAttr, PTHREAD_CREATE_JOINABLE);
     int code = pthread_create(&pConn->thread, &thAttr, taosRecvUdpData, pConn);
-    pthread_attr_destroy(&thAttr);
     if (code != 0) {
-      tError("%s failed to create thread to process UDP data, reason:%s", label, strerror(errno));
-      taosCloseSocket(pConn->fd);
-      taosCleanUpUdpConnection(pSet);
-      return NULL;
+      tError("%s failed to create thread to process UDP data(%s)", label, strerror(errno));
+      break;
     }
-
-    ++pSet->threads;
   }
 
-  tTrace("%s UDP connection is initialized, ip:%x port:%hu threads:%d", label, ip, port, threads);
+  pthread_attr_destroy(&thAttr);
 
+  if (i != threads) { 
+    terrno = TAOS_SYSTEM_ERROR(errno);
+    taosCleanUpUdpConnection(pSet);
+    return NULL;
+  }
+
+  tTrace("%s UDP connection is initialized, ip:%x:%hu threads:%d", label, ip, port, threads);
   return pSet;
 }
 
@@ -136,16 +141,17 @@ void taosCleanUpUdpConnection(void *handle) {
   for (int i = 0; i < pSet->threads; ++i) {
     pConn = pSet->udpConn + i;
     pConn->signature = NULL;
+
     // shutdown to signal the thread to exit
-    shutdown(pConn->fd, SHUT_RD);
+    if ( pConn->fd >=0) shutdown(pConn->fd, SHUT_RD);
   }
 
   for (int i = 0; i < pSet->threads; ++i) {
     pConn = pSet->udpConn + i;
-    pthread_join(pConn->thread, NULL);
-    free(pConn->buffer);
-    taosCloseSocket(pConn->fd);
-    tTrace("chandle:%p is closed", pConn);
+    if (pConn->thread) pthread_join(pConn->thread, NULL);
+    if (pConn->fd >=0) taosCloseSocket(pConn->fd);
+    tfree(pConn->buffer);
+    tTrace("UDP chandle:%p is closed", pConn);
   }
 
   tfree(pSet);
@@ -159,7 +165,7 @@ void *taosOpenUdpConnection(void *shandle, void *thandle, uint32_t ip, uint16_t
   SUdpConn *pConn = pSet->udpConn + pSet->index;
   pConn->port = port;
 
-  tTrace("%s UDP connection is setup, ip:%x:%hu, local:%x:%d", pConn->label, ip, port, pSet->ip, pConn->localPort);
+  tTrace("%s UDP connection is setup, ip:%x:%hu", pConn->label, ip, port);
 
   return pConn;
 }
diff --git a/tests/pytest/crash_gen.py b/tests/pytest/crash_gen.py
index dfd2034f7e..c88683aa09 100755
--- a/tests/pytest/crash_gen.py
+++ b/tests/pytest/crash_gen.py
@@ -730,13 +730,15 @@ class DbState():
     # when we re-run the test in 3 minutes (180 seconds), basically we should expand time duration
     # by a factor of 500.
     # TODO: what if it goes beyond 10 years into the future
+    # TODO: fix the error as result of above: "tsdb timestamp is out of range"
     def setupLastTick(self):
-        t1 = datetime.datetime(2020, 5, 30)
+        t1 = datetime.datetime(2020, 6, 1)
         t2 = datetime.datetime.now()
-        elSec = t2.timestamp() - t1.timestamp()
+        elSec = int(t2.timestamp() - t1.timestamp()) # maybe a very large number, takes 69 years to exceed Python int range
+        elSec2 = (  elSec % (8 * 12 * 30 * 24 * 60 * 60 / 500 ) ) * 500 # a number representing seconds within 10 years
         # print("elSec = {}".format(elSec))
         t3 = datetime.datetime(2012, 1, 1) # default "keep" is 10 years
-        t4 = datetime.datetime.fromtimestamp( t3.timestamp() + elSec * 500) # see explanation above
+        t4 = datetime.datetime.fromtimestamp( t3.timestamp() + elSec2) # see explanation above
         logger.info("Setting up TICKS to start from: {}".format(t4))
         return t4
 
@@ -963,7 +965,7 @@ class Task():
         try:
             self._executeInternal(te, wt) # TODO: no return value?
         except taos.error.ProgrammingError as err:
-            self.logDebug("[=] Taos library exception: errno={}, msg: {}".format(err.errno, err))
+            self.logDebug("[=] Taos library exception: errno={:X}, msg: {}".format(err.errno, err))
             self._err = err
         except:
             self.logDebug("[=] Unexpected exception")
diff --git a/tests/pytest/random-test/random-test-multi-threading-3.py b/tests/pytest/random-test/random-test-multi-threading-3.py
index db85ce2fe0..cab17c4c1a 100644
--- a/tests/pytest/random-test/random-test-multi-threading-3.py
+++ b/tests/pytest/random-test/random-test-multi-threading-3.py
@@ -205,7 +205,7 @@ class Test (Thread):
         global written
 
         dnodesDir = tdDnodes.getDnodesRootDir()
-        dataDir = dnodesDir + '/dnode1/*'
+        dataDir = dnodesDir + '/dnode1/data/*'
         deleteCmd = 'rm -rf %s' % dataDir
         os.system(deleteCmd)
 
diff --git a/tests/pytest/random-test/random-test-multi-threading.py b/tests/pytest/random-test/random-test-multi-threading.py
index 7d1a8a155d..1d8a5c3c82 100644
--- a/tests/pytest/random-test/random-test-multi-threading.py
+++ b/tests/pytest/random-test/random-test-multi-threading.py
@@ -208,7 +208,7 @@ class Test (threading.Thread):
         global written
 
         dnodesDir = tdDnodes.getDnodesRootDir()
-        dataDir = dnodesDir + '/dnode1/*'
+        dataDir = dnodesDir + '/dnode1/data/*'
         deleteCmd = 'rm -rf %s' % dataDir
         os.system(deleteCmd)
 
diff --git a/tests/pytest/stream/stream1.py b/tests/pytest/stream/stream1.py
index 7a9d88da3b..3b88b4f9f3 100644
--- a/tests/pytest/stream/stream1.py
+++ b/tests/pytest/stream/stream1.py
@@ -31,21 +31,26 @@ class TDTestCase:
         tdSql.prepare()
 
         tdLog.info("===== step1 =====")
-        tdSql.execute("create table stb0(ts timestamp, col1 int, col2 float) tags(tgcol int)")
+        tdSql.execute(
+            "create table stb0(ts timestamp, col1 int, col2 float) tags(tgcol int)")
         for i in range(tbNum):
             tdSql.execute("create table tb%d using stb0 tags(%d)" % (i, i))
             for j in range(rowNum):
-                tdSql.execute("insert into tb%d values (now - %dm, %d, %d)" % (i, 1440 - j, j, j))
+                tdSql.execute(
+                    "insert into tb%d values (now - %dm, %d, %d)" %
+                    (i, 1440 - j, j, j))
         time.sleep(0.1)
 
         tdLog.info("===== step2 =====")
-        tdSql.query("select count(*), count(col1), count(col2) from tb0 interval(1d)")
+        tdSql.query(
+            "select count(*), count(col1), count(col2) from tb0 interval(1d)")
         tdSql.checkData(0, 1, rowNum)
         tdSql.checkData(0, 2, rowNum)
         tdSql.checkData(0, 3, rowNum)
         tdSql.query("show tables")
         tdSql.checkRows(tbNum)
-        tdSql.execute("create table s0 as select count(*), count(col1), count(col2) from tb0 interval(1d)")
+        tdSql.execute(
+            "create table s0 as select count(*), count(col1), count(col2) from tb0 interval(1d)")
         tdSql.query("show tables")
         tdSql.checkRows(tbNum + 1)
 
@@ -67,7 +72,8 @@ class TDTestCase:
 
         tdLog.info("===== step6 =====")
         time.sleep(0.1)
-        tdSql.execute("create table s0 as select count(*), count(col1), count(col2) from tb0 interval(1d)")
+        tdSql.execute(
+            "create table s0 as select count(*), count(col1), count(col2) from tb0 interval(1d)")
         tdSql.query("show tables")
         tdSql.checkRows(tbNum + 1)
 
@@ -81,14 +87,16 @@ class TDTestCase:
         tdSql.checkData(0, 3, rowNum)
 
         tdLog.info("===== step8 =====")
-        tdSql.query("select count(*), count(col1), count(col2) from stb0 interval(1d)")
+        tdSql.query(
+            "select count(*), count(col1), count(col2) from stb0 interval(1d)")
         tdSql.checkData(0, 1, rowNum * tbNum)
         tdSql.checkData(0, 2, rowNum * tbNum)
         tdSql.checkData(0, 3, rowNum * tbNum)
         tdSql.query("show tables")
         tdSql.checkRows(tbNum + 1)
 
-        tdSql.execute("create table s1 as select count(*), count(col1), count(col2) from stb0 interval(1d)")
+        tdSql.execute(
+            "create table s1 as select count(*), count(col1), count(col2) from stb0 interval(1d)")
         tdSql.query("show tables")
         tdSql.checkRows(tbNum + 2)
 
@@ -110,7 +118,8 @@ class TDTestCase:
         tdSql.error("select * from s1")
 
         tdLog.info("===== step12 =====")
-        tdSql.execute("create table s1 as select count(*), count(col1), count(col2) from stb0 interval(1d)")
+        tdSql.execute(
+            "create table s1 as select count(*), count(col1), count(col2) from stb0 interval(1d)")
         tdSql.query("show tables")
         tdSql.checkRows(tbNum + 2)
 
diff --git a/tests/pytest/stream/stream2.py b/tests/pytest/stream/stream2.py
index 96eff3131d..7b77dc7793 100644
--- a/tests/pytest/stream/stream2.py
+++ b/tests/pytest/stream/stream2.py
@@ -24,7 +24,6 @@ class TDTestCase:
         tdLog.debug("start to execute %s" % __file__)
         tdSql.init(conn.cursor(), logSql)
 
-
     def run(self):
         tbNum = 10
         rowNum = 20
@@ -33,11 +32,14 @@ class TDTestCase:
         tdSql.prepare()
 
         tdLog.info("===== step1 =====")
-        tdSql.execute("create table stb0(ts timestamp, col1 int, col2 float) tags(tgcol int)")
+        tdSql.execute(
+            "create table stb0(ts timestamp, col1 int, col2 float) tags(tgcol int)")
         for i in range(tbNum):
             tdSql.execute("create table tb%d using stb0 tags(%d)" % (i, i))
             for j in range(rowNum):
-                tdSql.execute("insert into tb%d values (now - %dm, %d, %d)" % (i, 1440 - j, j, j))
+                tdSql.execute(
+                    "insert into tb%d values (now - %dm, %d, %d)" %
+                    (i, 1440 - j, j, j))
         time.sleep(0.1)
 
         tdLog.info("===== step2 =====")
@@ -45,7 +47,8 @@ class TDTestCase:
         tdSql.checkData(0, 1, rowNum)
         tdSql.query("show tables")
         tdSql.checkRows(tbNum)
-        tdSql.execute("create table s0 as select count(col1) from tb0 interval(1d)")
+        tdSql.execute(
+            "create table s0 as select count(col1) from tb0 interval(1d)")
         tdSql.query("show tables")
         tdSql.checkRows(tbNum + 1)
 
@@ -63,7 +66,8 @@ class TDTestCase:
         tdSql.error("select * from s0")
 
         tdLog.info("===== step6 =====")
-        tdSql.execute("create table s0 as select count(*), count(col1), count(col2) from tb0 interval(1d)")
+        tdSql.execute(
+            "create table s0 as select count(*), count(col1), count(col2) from tb0 interval(1d)")
         tdSql.query("show tables")
         tdSql.checkRows(tbNum + 1)
 
@@ -75,13 +79,15 @@ class TDTestCase:
         tdSql.checkData(0, 3, rowNum)
 
         tdLog.info("===== step8 =====")
-        tdSql.query("select count(*), count(col1), count(col2) from stb0 interval(1d)")
+        tdSql.query(
+            "select count(*), count(col1), count(col2) from stb0 interval(1d)")
         tdSql.checkData(0, 1, totalNum)
         tdSql.checkData(0, 2, totalNum)
         tdSql.checkData(0, 3, totalNum)
         tdSql.query("show tables")
         tdSql.checkRows(tbNum + 1)
-        tdSql.execute("create table s1 as select count(*), count(col1), count(col2) from stb0 interval(1d)")
+        tdSql.execute(
+            "create table s1 as select count(*), count(col1), count(col2) from stb0 interval(1d)")
         tdSql.query("show tables")
         tdSql.checkRows(tbNum + 2)
 
@@ -101,7 +107,8 @@ class TDTestCase:
         tdSql.error("select * from s1")
 
         tdLog.info("===== step12 =====")
-        tdSql.execute("create table s1 as select count(col1) from stb0 interval(1d)")
+        tdSql.execute(
+            "create table s1 as select count(col1) from stb0 interval(1d)")
         tdSql.query("show tables")
         tdSql.checkRows(tbNum + 2)
 
@@ -112,7 +119,6 @@ class TDTestCase:
         #tdSql.checkData(0, 2, None)
         #tdSql.checkData(0, 3, None)
 
-
     def stop(self):
         tdSql.close()
         tdLog.success("%s successfully executed" % __file__)
diff --git a/tests/pytest/util/dnodes.py b/tests/pytest/util/dnodes.py
index f3ccd58432..e24af473f3 100644
--- a/tests/pytest/util/dnodes.py
+++ b/tests/pytest/util/dnodes.py
@@ -319,6 +319,7 @@ class TDDnodes:
         self.dnodes.append(TDDnode(8))
         self.dnodes.append(TDDnode(9))
         self.dnodes.append(TDDnode(10))
+        self.simDeployed = False
 
     def init(self, path):
         psCmd = "ps -ef|grep -w taosd| grep -v grep | awk '{print $2}'"
@@ -378,7 +379,10 @@ class TDDnodes:
         self.sim = TDSimClient()
         self.sim.init(self.path)
         self.sim.setTestCluster(self.testCluster)
-        self.sim.deploy()
+
+        if (self.simDeployed == False):
+            self.sim.deploy()
+            self.simDeployed = True
 
         self.check(index)
         self.dnodes[index - 1].setTestCluster(self.testCluster)