diff --git a/src/balance/src/balance.c b/src/balance/src/balance.c
index 0d2d9fc778b437b8fe0671487da097f6c531b204..2b1888042c0645a93ae08fe9438085f96e547b71 100644
--- a/src/balance/src/balance.c
+++ b/src/balance/src/balance.c
@@ -165,7 +165,7 @@ int32_t balanceAllocVnodes(SVgObj *pVgroup) {
       balanceSwapVnodeGid(pVgroup->vnodeGid, pVgroup->vnodeGid + 1);
     }
   } else {
-    int32_t randVal = rand() % 6;
+    int32_t randVal = randIndex++ % 6;
     if (randVal == 1) {  // 1, 0, 2
       balanceSwapVnodeGid(pVgroup->vnodeGid + 0, pVgroup->vnodeGid + 1);
     } else if (randVal == 2) {  // 1, 2, 0
diff --git a/src/plugins/mqtt/src/mqttSystem.c b/src/plugins/mqtt/src/mqttSystem.c
index ab3f3f5d841bbfd5c2c2f7cd439c445ccaae93b2..69810e27858040391e80fd39fea6af1ea8d4d96c 100644
--- a/src/plugins/mqtt/src/mqttSystem.c
+++ b/src/plugins/mqtt/src/mqttSystem.c
@@ -39,6 +39,7 @@ int                      mttIsRuning = 1;
 
 int32_t mqttInitSystem() {
   int   rc = 0;
+#if 0
   uint8_t sendbuf[2048];
   uint8_t recvbuf[1024];
   recntStatus.sendbuf = sendbuf;
@@ -47,7 +48,11 @@ int32_t mqttInitSystem() {
   recntStatus.recvbufsz = sizeof(recvbuf);
   char* url = tsMqttBrokerAddress;
   recntStatus.user_name = strstr(url, "@") != NULL ? strbetween(url, "//", ":") : NULL;
-  recntStatus.password = strstr(url, "@") != NULL ? strbetween(strstr(url, recntStatus.user_name), ":", "@") : NULL;
+  
+  char * passStr = strstr(url, recntStatus.user_name);
+  if (passStr != NULL) {
+    recntStatus.password = strstr(url, "@") != NULL ? strbetween(passStr, ":", "@") : NULL;
+  }
 
   if (strlen(url) == 0) {
     mqttDebug("mqtt module not init, url is null");
@@ -91,11 +96,13 @@ int32_t mqttInitSystem() {
     topicPath = NULL;
   }
   
+#endif  
   return rc;
 }
 
 int32_t mqttStartSystem() {
   int rc = 0;
+#if 0  
   if (recntStatus.user_name != NULL && recntStatus.password != NULL) {
     mqttInfo("connecting to  mqtt://%s:%s@%s:%s/%s/", recntStatus.user_name, recntStatus.password,
               recntStatus.hostname, recntStatus.port, topicPath);
@@ -112,18 +119,22 @@ int32_t mqttStartSystem() {
   } else {
     mqttInfo("listening for '%s' messages.", recntStatus.topic);
   }
+#endif
   return rc;
 }
 
 void mqttStopSystem() {
+#if 0  
   mqttClient.error = MQTT_ERROR_SOCKET_ERROR;
   mttIsRuning = 0;
   usleep(300000U);
   mqttCleanup(EXIT_SUCCESS, mqttClient.socketfd, &clientDaemonThread);
   mqttInfo("mqtt is stoped");
+#endif  
 }
 
 void mqttCleanUpSystem() {
+#if 0
   mqttInfo("starting to cleanup mqtt");
   free(recntStatus.user_name);
   free(recntStatus.password);
@@ -132,6 +143,7 @@ void mqttCleanUpSystem() {
   free(recntStatus.topic);
   free(topicPath);
   mqttInfo("mqtt is cleaned up");
+#endif  
 }
 
 void mqtt_PublishCallback(void** unused, struct mqtt_response_publish* published) {
@@ -183,9 +195,11 @@ void* mqttClientRefresher(void* client) {
 }
 
 void mqttCleanup(int status, int sockfd, pthread_t* client_daemon) {
+#if 0 
   mqttInfo("clean up mqtt module");
   if (sockfd != -1) close(sockfd);
   if (client_daemon != NULL) pthread_cancel(*client_daemon);
+#endif
 }
 
 void mqttInitConnCb(void* param, TAOS_RES* result, int32_t code) {
diff --git a/src/util/src/tsocket.c b/src/util/src/tsocket.c
index 23f2e5f00ae339937a9812ca0deab901275e6a89..2de3490459308d84aaea47f31a1c38adf7075b84 100644
--- a/src/util/src/tsocket.c
+++ b/src/util/src/tsocket.c
@@ -231,8 +231,9 @@ SOCKET taosOpenUdpSocket(uint32_t ip, uint16_t port) {
   localAddr.sin_addr.s_addr = ip;
   localAddr.sin_port = (uint16_t)htons(port);
 
-  if ((sockFd = (int)socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+  if ((sockFd = (int)socket(AF_INET, SOCK_DGRAM, 0)) <= 2) {
     uError("failed to open udp socket: %d (%s)", errno, strerror(errno));
+    close(sockFd);
     return -1;
   }
 
@@ -265,8 +266,9 @@ SOCKET taosOpenTcpClientSocket(uint32_t destIp, uint16_t destPort, uint32_t clie
 
   sockFd = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
 
-  if (sockFd < 0) {
+  if (sockFd <= 2) {
     uError("failed to open the socket: %d (%s)", errno, strerror(errno));
+    close(sockFd);
     return -1;
   }
 
@@ -276,7 +278,7 @@ SOCKET taosOpenTcpClientSocket(uint32_t destIp, uint16_t destPort, uint32_t clie
     uError("setsockopt SO_REUSEADDR failed: %d (%s)", errno, strerror(errno));
     taosCloseSocket(sockFd);
     return -1;
-  };
+  }
 
   if (clientIp != 0) {
     memset((char *)&clientAddr, 0, sizeof(clientAddr));
@@ -371,8 +373,9 @@ SOCKET taosOpenTcpServerSocket(uint32_t ip, uint16_t port) {
   serverAdd.sin_addr.s_addr = ip;
   serverAdd.sin_port = (uint16_t)htons(port);
 
-  if ((sockFd = (int)socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 2) {
+  if ((sockFd = (int)socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) <= 2) {
     uError("failed to open TCP socket: %d (%s)", errno, strerror(errno));
+    close(sockFd);
     return -1;
   }