diff --git a/src/rootserver/ob_heartbeat_service.cpp b/src/rootserver/ob_heartbeat_service.cpp
index ed9410730c..1aff65089d 100644
--- a/src/rootserver/ob_heartbeat_service.cpp
+++ b/src/rootserver/ob_heartbeat_service.cpp
@@ -410,6 +410,7 @@ int ObHeartbeatService::prepare_whitelist_()
     ret = OB_NOT_INIT;
     LOG_WARN("not init", KR(ret), K(is_inited_));
   } else if (OB_ISNULL(sql_proxy_)) {
+    ret = OB_ERR_UNEXPECTED;
     LOG_WARN("sql_proxy_ is null", KR(ret), KP(sql_proxy_));
   } else if (OB_FAIL(check_or_update_service_epoch_(epoch_id))) {
     LOG_WARN("fail to check or update service epoch", KR(ret), K(epoch_id));
diff --git a/src/rootserver/ob_ls_recovery_reportor.cpp b/src/rootserver/ob_ls_recovery_reportor.cpp
index 6270482597..6d98e3e75b 100755
--- a/src/rootserver/ob_ls_recovery_reportor.cpp
+++ b/src/rootserver/ob_ls_recovery_reportor.cpp
@@ -240,6 +240,7 @@ int ObLSRecoveryReportor::update_ls_recovery_stat_()
             storage::ObLSGetMod::RS_MOD))) {
       LOG_WARN("get log stream iter failed", KR(ret));
     } else if (OB_ISNULL(iter = guard.get_ptr())) {
+      ret = OB_ERR_UNEXPECTED;
       LOG_WARN("iter is NULL", KR(ret));
     } else {
       int tmp_ret = OB_SUCCESS;
@@ -438,6 +439,7 @@ int ObLSRecoveryReportor::update_replayable_point_from_meta_()
           storage::ObLSGetMod::RS_MOD))) {
     LOG_WARN("get log stream iter failed", KR(ret));
   } else if (OB_ISNULL(iter = guard.get_ptr())) {
+    ret = OB_ERR_UNEXPECTED;
     LOG_WARN("iter is NULL", KR(ret));
   } else {
     ObLS *ls = nullptr;
diff --git a/src/rootserver/ob_ls_service_helper.cpp b/src/rootserver/ob_ls_service_helper.cpp
index 526e69f603..d96d2e9041 100755
--- a/src/rootserver/ob_ls_service_helper.cpp
+++ b/src/rootserver/ob_ls_service_helper.cpp
@@ -1069,7 +1069,7 @@ int ObTenantLSInfo::gather_all_ls_info_()
         const share::ObLSStatusInfo &info = status_info_array.at(i);
         if (info.ls_is_wait_offline()) {
           //ls is already offline, no need to process
-        } else if (FAILEDx(add_ls_status_info_(info))) {
+        } else if (OB_FAIL(add_ls_status_info_(info))) {
           LOG_WARN("failed to add ls status info", KR(ret), K(i), K(info));
         }
       }// end for
diff --git a/src/rootserver/ob_root_service.cpp b/src/rootserver/ob_root_service.cpp
index 440703426f..06743d6b4c 100755
--- a/src/rootserver/ob_root_service.cpp
+++ b/src/rootserver/ob_root_service.cpp
@@ -1514,6 +1514,7 @@ int ObRootService::schedule_self_check_task()
     ret = OB_NOT_INIT;
     LOG_WARN("not init", K(ret));
   } else if (task_queue_.exist_timer_task(self_check_task_)) {
+    // ignore error
     LOG_WARN("already have one self_check_task, ignore this");
   } else if (OB_FAIL(task_queue_.add_timer_task(self_check_task_, delay, did_repeat))) {
     LOG_WARN("fail to add timer task", K(ret));
@@ -1531,6 +1532,7 @@ int ObRootService::schedule_update_rs_list_task()
     ret = OB_NOT_INIT;
     LOG_WARN("not init", K(ret));
   } else if (task_queue_.exist_timer_task(update_rs_list_timer_task_)) {
+    // ignore error
     LOG_WARN("already have one update rs list timer task , ignore this");
   } else if (OB_FAIL(task_queue_.add_timer_task(update_rs_list_timer_task_,
                                                 ObUpdateRsListTimerTask::RETRY_INTERVAL,
@@ -1550,7 +1552,8 @@ int ObRootService::schedule_update_all_server_config_task()
     ret = OB_NOT_INIT;
     LOG_WARN("not init", KR(ret), K(inited_));
   } else if (task_queue_.exist_timer_task(update_all_server_config_task_)) {
-    LOG_WARN("already have one update rs list timer task , ignore this");
+    // ignore error
+    LOG_WARN("already have one update_all_server_config task , ignore this");
   } else if (OB_FAIL(task_queue_.add_timer_task(
       update_all_server_config_task_,
       ALL_SERVER_SCHEDULE_ERROR ? (ObUpdateAllServerConfigTask::RETRY_INTERVAL / 2) : ObUpdateAllServerConfigTask::RETRY_INTERVAL,
@@ -1571,6 +1574,7 @@ int ObRootService::schedule_load_ddl_task()
     ret = OB_NOT_INIT;
     LOG_WARN("not init", K(ret));
   } else if (task_queue_.exist_timer_task(load_ddl_task_)) {
+    // ignore error
     LOG_WARN("load ddl task already exist", K(ret));
   } else if (OB_FAIL(task_queue_.add_timer_task(load_ddl_task_, delay, did_repeat))) {
     LOG_WARN("fail to add timer task", K(ret));
@@ -1589,6 +1593,7 @@ int ObRootService::schedule_refresh_io_calibration_task()
     ret = OB_NOT_INIT;
     LOG_WARN("not init", K(ret));
   } else if (task_queue_.exist_timer_task(refresh_io_calibration_task_)) {
+    // ignore error
     LOG_WARN("refresh io calibration task already exist", K(ret));
   } else if (OB_FAIL(task_queue_.add_timer_task(refresh_io_calibration_task_, delay, did_repeat))) {
     LOG_WARN("fail to add timer task", K(ret));