diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0925fa1a68c6506212cbbc6aaade09a04495ffdc..c4643c0adc0bbf006c9f734c5015e96e47dede52 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@ Please mark all change in change log and use the ticket from JIRA.
 # Milvus 0.5.1 (TODO)
 
 ## Bug
+- \#90 - The server start error messages could be improved to enhance user experience
 - \#104 - test_scheduler core dump
 
 ## Improvement
diff --git a/core/src/server/Config.cpp b/core/src/server/Config.cpp
index 7de84cbccc6944b4845c5fceaee751fc27e9d923..b20d6c2436cfa59c4b2bd46ab5585aabd3526f76 100644
--- a/core/src/server/Config.cpp
+++ b/core/src/server/Config.cpp
@@ -363,7 +363,9 @@ Config::PrintAll() {
 Status
 Config::CheckServerConfigAddress(const std::string& value) {
     if (!ValidationUtil::ValidateIpAddress(value).ok()) {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid server config address: " + value);
+        std::string msg = "Invalid server IP address: " + value
+                          + ". Possible reason: server_config.address is invalid in server_config.yaml.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     }
     return Status::OK();
 }
@@ -371,11 +373,15 @@ Config::CheckServerConfigAddress(const std::string& value) {
 Status
 Config::CheckServerConfigPort(const std::string& value) {
     if (!ValidationUtil::ValidateStringIsNumber(value).ok()) {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid server config port: " + value);
+        std::string msg = "Port " + value + " is not a number. "
+                          + "Possible reason: server_config.port in server_config.yaml is invalid.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     } else {
         int32_t port = std::stoi(value);
         if (!(port > 1024 && port < 65535)) {
-            return Status(SERVER_INVALID_ARGUMENT, "Server config port out of range (1024, 65535): " + value);
+            std::string msg = "Port " + value + " is not in range [1025, 65534]. "
+                              + "Possible reason: server_config.port in server_config.yaml is invalid.";
+            return Status(SERVER_INVALID_ARGUMENT, msg);
         }
     }
     return Status::OK();
@@ -385,7 +391,8 @@ Status
 Config::CheckServerConfigDeployMode(const std::string& value) {
     if (value != "single" && value != "cluster_readonly" && value != "cluster_writable") {
         return Status(SERVER_INVALID_ARGUMENT,
-                      "Invalid server config mode [single, cluster_readonly, cluster_writable]: " + value);
+                      "Error: server_config.deploy_mode in server_config.yaml is not one of "
+                      "single, cluster_readonly, and cluster_writable.");
     }
     return Status::OK();
 }
@@ -411,7 +418,8 @@ Config::CheckServerConfigTimeZone(const std::string& value) {
 Status
 Config::CheckDBConfigPrimaryPath(const std::string& value) {
     if (value.empty()) {
-        return Status(SERVER_INVALID_ARGUMENT, "DB config primary_path empty");
+        return Status(SERVER_INVALID_ARGUMENT,
+                      "db_path is empty. Possible reason: db_config.db_path in server_config.yaml is empty.");
     }
     return Status::OK();
 }
@@ -424,7 +432,11 @@ Config::CheckDBConfigSecondaryPath(const std::string& value) {
 Status
 Config::CheckDBConfigBackendUrl(const std::string& value) {
     if (!ValidationUtil::ValidateDbURI(value).ok()) {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid DB config backend_url: " + value);
+        std::string msg =
+            "Invalid db_backend_url: " + value
+            + ". Possible reason: db_config.db_backend_url is invalid in server_config.yaml. "
+            + "The correct format should be like sqlite://:@:/ or mysql://root:123456@127.0.0.1:3306/milvus.";
+        return Status(SERVER_INVALID_ARGUMENT, "invalid db_backend_url: " + value);
     }
     return Status::OK();
 }
@@ -432,7 +444,9 @@ Config::CheckDBConfigBackendUrl(const std::string& value) {
 Status
 Config::CheckDBConfigArchiveDiskThreshold(const std::string& value) {
     if (!ValidationUtil::ValidateStringIsNumber(value).ok()) {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid DB config archive_disk_threshold: " + value);
+        std::string msg = "Invalid archive disk threshold: " + value
+                          + "Possible reason: db_config.archive_disk_threshold in server_config.yaml is invalid.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     }
     return Status::OK();
 }
@@ -440,7 +454,9 @@ Config::CheckDBConfigArchiveDiskThreshold(const std::string& value) {
 Status
 Config::CheckDBConfigArchiveDaysThreshold(const std::string& value) {
     if (!ValidationUtil::ValidateStringIsNumber(value).ok()) {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid DB config archive_days_threshold: " + value);
+        std::string msg = "Invalid archive days threshold: " + value
+                          + "Possible reason: db_config.archive_disk_threshold in server_config.yaml is invalid.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     }
     return Status::OK();
 }
@@ -448,13 +464,17 @@ Config::CheckDBConfigArchiveDaysThreshold(const std::string& value) {
 Status
 Config::CheckDBConfigInsertBufferSize(const std::string& value) {
     if (!ValidationUtil::ValidateStringIsNumber(value).ok()) {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid DB config insert_buffer_size: " + value);
+        std::string msg = "Invalid insert buffer size: " + value
+                          + "Possible reason: db_config.insert_buffer_size in server_config.yaml is invalid.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     } else {
         int64_t buffer_size = std::stoi(value) * GB;
         uint64_t total_mem = 0, free_mem = 0;
         CommonUtil::GetSystemMemInfo(total_mem, free_mem);
         if (buffer_size >= total_mem) {
-            return Status(SERVER_INVALID_ARGUMENT, "DB config insert_buffer_size exceed system memory: " + value);
+            std::string msg = "Invalid insert buffer size: " + value
+                              + "Possible reason: insert buffer size exceed system memory.";
+            return Status(SERVER_INVALID_ARGUMENT, msg);
         }
     }
     return Status::OK();
@@ -463,7 +483,9 @@ Config::CheckDBConfigInsertBufferSize(const std::string& value) {
 Status
 Config::CheckMetricConfigEnableMonitor(const std::string& value) {
     if (!ValidationUtil::ValidateStringIsBool(value).ok()) {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid metric config auto_bootup: " + value);
+        std::string msg = "Invalid metric config: " + value
+                          + "Possible reason: metric_config.enable_monitor is invalid.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     }
     return Status::OK();
 }
@@ -471,7 +493,9 @@ Config::CheckMetricConfigEnableMonitor(const std::string& value) {
 Status
 Config::CheckMetricConfigCollector(const std::string& value) {
     if (value != "prometheus") {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid metric config collector: " + value);
+        std::string msg = "Invalid metric config: " + value
+                          + "Possible reason: metric_config.collector is invalid.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     }
     return Status::OK();
 }
@@ -479,6 +503,8 @@ Config::CheckMetricConfigCollector(const std::string& value) {
 Status
 Config::CheckMetricConfigPrometheusPort(const std::string& value) {
     if (!ValidationUtil::ValidateStringIsNumber(value).ok()) {
+        std::string msg = "Invalid metric config: " + value
+                          + "Possible reason: metric_config.prometheus_config.port is invalid.";
         return Status(SERVER_INVALID_ARGUMENT, "Invalid metric config prometheus_port: " + value);
     }
     return Status::OK();
@@ -487,15 +513,19 @@ Config::CheckMetricConfigPrometheusPort(const std::string& value) {
 Status
 Config::CheckCacheConfigCpuCacheCapacity(const std::string& value) {
     if (!ValidationUtil::ValidateStringIsNumber(value).ok()) {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid cache config cpu_cache_capacity: " + value);
+        std::string msg = "Invalid cpu cache capacity: " + value
+                          + "Possible reason: cache_config.cpu_cache_capacity is invalid.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     } else {
         uint64_t cpu_cache_capacity = std::stoi(value) * GB;
         uint64_t total_mem = 0, free_mem = 0;
         CommonUtil::GetSystemMemInfo(total_mem, free_mem);
         if (cpu_cache_capacity >= total_mem) {
-            return Status(SERVER_INVALID_ARGUMENT, "Cache config cpu_cache_capacity exceed system memory: " + value);
+            std::string msg = "Invalid cpu cache capacity: " + value
+                              + "Possible reason: Cache config cpu_cache_capacity exceed system memory.";
+            return Status(SERVER_INVALID_ARGUMENT, msg);
         } else if (cpu_cache_capacity > static_cast<double>(total_mem * 0.9)) {
-            std::cerr << "Warning: cpu_cache_capacity value is too big" << std::endl;
+            std::cerr << "WARNING: cpu cache capacity value is too big" << std::endl;
         }
 
         int32_t buffer_value;
@@ -506,7 +536,10 @@ Config::CheckCacheConfigCpuCacheCapacity(const std::string& value) {
 
         int64_t insert_buffer_size = buffer_value * GB;
         if (insert_buffer_size + cpu_cache_capacity >= total_mem) {
-            return Status(SERVER_INVALID_ARGUMENT, "Sum of cpu_cache_capacity and buffer_size exceed system memory");
+            std::string msg = "Invalid cpu cache capacity: " + value
+                              + "Possible reason: sum of cache_config.cpu_cache_capacity and "
+                                "db_config.insert_buffer_size exceeds system memory.";
+            return Status(SERVER_INVALID_ARGUMENT, msg);
         }
     }
     return Status::OK();
@@ -515,11 +548,15 @@ Config::CheckCacheConfigCpuCacheCapacity(const std::string& value) {
 Status
 Config::CheckCacheConfigCpuCacheThreshold(const std::string& value) {
     if (!ValidationUtil::ValidateStringIsFloat(value).ok()) {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid cache config cpu_cache_threshold: " + value);
+        std::string msg = "Invalid cpu cache threshold: " + value
+                          + "Possible reason: cache_config.cpu_cache_threshold is invalid.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     } else {
         float cpu_cache_threshold = std::stof(value);
         if (cpu_cache_threshold <= 0.0 || cpu_cache_threshold >= 1.0) {
-            return Status(SERVER_INVALID_ARGUMENT, "Invalid cache config cpu_cache_threshold: " + value);
+            std::string msg = "Invalid cpu cache threshold: " + value
+                              + "Possible reason: cache_config.cpu_cache_threshold is invalid.";
+            return Status(SERVER_INVALID_ARGUMENT, msg);
         }
     }
     return Status::OK();
@@ -528,7 +565,9 @@ Config::CheckCacheConfigCpuCacheThreshold(const std::string& value) {
 Status
 Config::CheckCacheConfigGpuCacheCapacity(const std::string& value) {
     if (!ValidationUtil::ValidateStringIsNumber(value).ok()) {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid cache config gpu_cache_capacity: " + value);
+        std::string msg = "Invalid gpu cache capacity: " + value
+                          + "Possible reason: cache_config.gpu_cache_capacity is invalid.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     } else {
         uint64_t gpu_cache_capacity = std::stoi(value) * GB;
         int gpu_index;
@@ -539,13 +578,14 @@ Config::CheckCacheConfigGpuCacheCapacity(const std::string& value) {
 
         size_t gpu_memory;
         if (!ValidationUtil::GetGpuMemory(gpu_index, gpu_memory).ok()) {
-            return Status(SERVER_UNEXPECTED_ERROR,
-                          "Fail to get GPU memory for GPU device: " + std::to_string(gpu_index));
+            std::string msg = "Fail to get GPU memory for GPU device: " + std::to_string(gpu_index);
+            return Status(SERVER_UNEXPECTED_ERROR, msg);
         } else if (gpu_cache_capacity >= gpu_memory) {
-            return Status(SERVER_INVALID_ARGUMENT,
-                          "Cache config gpu_cache_capacity exceed GPU memory: " + std::to_string(gpu_memory));
+            std::string msg = "Invalid gpu cache capacity: " + value
+                              + "Possible reason: cache_config.gpu_cache_capacity exceed GPU memory.";
+            return Status(SERVER_INVALID_ARGUMENT, msg);
         } else if (gpu_cache_capacity > (double)gpu_memory * 0.9) {
-            std::cerr << "Warning: gpu_cache_capacity value is too big" << std::endl;
+            std::cerr << "Warning: gpu cache capacity value is too big" << std::endl;
         }
     }
     return Status::OK();
@@ -554,11 +594,15 @@ Config::CheckCacheConfigGpuCacheCapacity(const std::string& value) {
 Status
 Config::CheckCacheConfigGpuCacheThreshold(const std::string& value) {
     if (!ValidationUtil::ValidateStringIsFloat(value).ok()) {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid cache config gpu_cache_threshold: " + value);
+        std::string msg = "Invalid gpu cache threshold: " + value
+                          + "Possible reason: cache_config.gpu_cache_threshold is invalid.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     } else {
         float gpu_cache_threshold = std::stof(value);
         if (gpu_cache_threshold <= 0.0 || gpu_cache_threshold >= 1.0) {
-            return Status(SERVER_INVALID_ARGUMENT, "Invalid cache config gpu_cache_threshold: " + value);
+            std::string msg = "Invalid gpu cache threshold: " + value
+                              + "Possible reason: cache_config.gpu_cache_threshold is invalid.";
+            return Status(SERVER_INVALID_ARGUMENT, msg);
         }
     }
     return Status::OK();
@@ -567,7 +611,9 @@ Config::CheckCacheConfigGpuCacheThreshold(const std::string& value) {
 Status
 Config::CheckCacheConfigCacheInsertData(const std::string& value) {
     if (!ValidationUtil::ValidateStringIsBool(value).ok()) {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid cache config cache_insert_data: " + value);
+        std::string msg = "Invalid cache insert option: " + value
+                          + "Possible reason: cache_config.cache_insert_data is invalid.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     }
     return Status::OK();
 }
@@ -575,7 +621,9 @@ Config::CheckCacheConfigCacheInsertData(const std::string& value) {
 Status
 Config::CheckEngineConfigUseBlasThreshold(const std::string& value) {
     if (!ValidationUtil::ValidateStringIsNumber(value).ok()) {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid engine config use_blas_threshold: " + value);
+        std::string msg = "Invalid blas threshold: " + value
+                          + "Possible reason: engine_config.use_blas_threshold is invalid.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     }
     return Status::OK();
 }
@@ -583,14 +631,18 @@ Config::CheckEngineConfigUseBlasThreshold(const std::string& value) {
 Status
 Config::CheckEngineConfigOmpThreadNum(const std::string& value) {
     if (!ValidationUtil::ValidateStringIsNumber(value).ok()) {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid engine config omp_thread_num: " + value);
+        std::string msg = "Invalid omp thread number: " + value
+                          + "Possible reason: engine_config.omp_thread_num is invalid.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     }
 
     int32_t omp_thread = std::stoi(value);
     uint32_t sys_thread_cnt = 8;
     CommonUtil::GetSystemAvailableThreads(sys_thread_cnt);
     if (omp_thread > static_cast<int32_t>(sys_thread_cnt)) {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid engine config omp_thread_num: " + value);
+        std::string msg = "Invalid omp thread number: " + value
+                          + "Possible reason: engine_config.omp_thread_num is invalid.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     }
     return Status::OK();
 }
@@ -598,7 +650,9 @@ Config::CheckEngineConfigOmpThreadNum(const std::string& value) {
 Status
 Config::CheckResourceConfigMode(const std::string& value) {
     if (value != "simple") {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid resource config mode: " + value);
+        std::string msg = "Invalid resource mode: " + value
+                          + "Possible reason: resource_config.mode is invalid.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     }
     return Status::OK();
 }
@@ -608,12 +662,16 @@ CheckGpuDevice(const std::string& value) {
     const std::regex pat("gpu(\\d+)");
     std::cmatch m;
     if (!std::regex_match(value.c_str(), m, pat)) {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid gpu device: " + value);
+        std::string msg = "Invalid gpu device: " + value
+                          + "Possible reason: resource_config.search_resources is invalid.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     }
 
     int32_t gpu_index = std::stoi(value.substr(3));
     if (!ValidationUtil::ValidateGpuIndex(gpu_index).ok()) {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid gpu device: " + value);
+        std::string msg = "Invalid gpu device: " + value
+                          + "Possible reason: resource_config.search_resources is invalid.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     }
     return Status::OK();
 }
@@ -621,11 +679,15 @@ CheckGpuDevice(const std::string& value) {
 Status
 Config::CheckResourceConfigSearchResources(const std::vector<std::string>& value) {
     if (value.empty()) {
-        return Status(SERVER_INVALID_ARGUMENT, "Empty resource config search_resources");
+        std::string msg = "Invalid search resource. "
+                          "Possible reason: resource_config.search_resources is empty.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     }
 
     for (auto& gpu_device : value) {
         if (!CheckGpuDevice(gpu_device).ok()) {
+            std::string msg = "Invalid search resource: " + gpu_device
+                              + "Possible reason: resource_config.search_resources is invalid.";
             return Status(SERVER_INVALID_ARGUMENT, "Invalid resource config search_resources: " + gpu_device);
         }
     }
@@ -635,7 +697,9 @@ Config::CheckResourceConfigSearchResources(const std::vector<std::string>& value
 Status
 Config::CheckResourceConfigIndexBuildDevice(const std::string& value) {
     if (!CheckGpuDevice(value).ok()) {
-        return Status(SERVER_INVALID_ARGUMENT, "Invalid resource config index_build_device: " + value);
+        std::string msg = "Invalid index build device: " + value
+                          + "Possible reason: resource_config.index_build_device is invalid.";
+        return Status(SERVER_INVALID_ARGUMENT, msg);
     }
     return Status::OK();
 }
diff --git a/core/src/server/DBWrapper.cpp b/core/src/server/DBWrapper.cpp
index a5b892ad47350a7b45d1c337500ca1fac84e4da3..2217b29e1c8fe54d36510b55504e15cbfbdc2d9d 100644
--- a/core/src/server/DBWrapper.cpp
+++ b/core/src/server/DBWrapper.cpp
@@ -54,7 +54,8 @@ DBWrapper::StartService() {
     std::string db_slave_path;
     s = config.GetDBConfigSecondaryPath(db_slave_path);
     if (!s.ok()) {
-        return s;
+        std::cerr << s.ToString() << std::endl;
+        kill(0, SIGUSR1);
     }
 
     StringHelpFunctions::SplitStringByDelimeter(db_slave_path, ";", opt.meta_.slave_paths_);
@@ -62,13 +63,15 @@ DBWrapper::StartService() {
     // cache config
     s = config.GetCacheConfigCacheInsertData(opt.insert_cache_immediately_);
     if (!s.ok()) {
-        return s;
+        std::cerr << s.ToString() << std::endl;
+        kill(0, SIGUSR1);
     }
 
     std::string mode;
     s = config.GetServerConfigDeployMode(mode);
     if (!s.ok()) {
-        return s;
+        std::cerr << s.ToString() << std::endl;
+        kill(0, SIGUSR1);
     }
 
     if (mode == "single") {
@@ -78,7 +81,8 @@ DBWrapper::StartService() {
     } else if (mode == "cluster_writable") {
         opt.mode_ = engine::DBOptions::MODE::CLUSTER_WRITABLE;
     } else {
-        std::cerr << "ERROR: mode specified in server_config must be ['single', 'cluster_readonly', 'cluster_writable']"
+        std::cerr << "Error: server_config.deploy_mode in server_config.yaml is not one of "
+                  << "single, cluster_readonly, and cluster_writable."
                   << std::endl;
         kill(0, SIGUSR1);
     }
@@ -87,7 +91,8 @@ DBWrapper::StartService() {
     int32_t omp_thread;
     s = config.GetEngineConfigOmpThreadNum(omp_thread);
     if (!s.ok()) {
-        return s;
+        std::cerr << s.ToString() << std::endl;
+        kill(0, SIGUSR1);
     }
 
     if (omp_thread > 0) {
@@ -105,7 +110,8 @@ DBWrapper::StartService() {
     int32_t use_blas_threshold;
     s = config.GetEngineConfigUseBlasThreshold(use_blas_threshold);
     if (!s.ok()) {
-        return s;
+        std::cerr << s.ToString() << std::endl;
+        kill(0, SIGUSR1);
     }
 
     faiss::distance_compute_blas_threshold = use_blas_threshold;
@@ -115,7 +121,8 @@ DBWrapper::StartService() {
     int32_t disk, days;
     s = config.GetDBConfigArchiveDiskThreshold(disk);
     if (!s.ok()) {
-        return s;
+        std::cerr << s.ToString() << std::endl;
+        kill(0, SIGUSR1);
     }
 
     if (disk > 0) {
@@ -124,7 +131,8 @@ DBWrapper::StartService() {
 
     s = config.GetDBConfigArchiveDaysThreshold(days);
     if (!s.ok()) {
-        return s;
+        std::cerr << s.ToString() << std::endl;
+        kill(0, SIGUSR1);
     }
 
     if (days > 0) {
@@ -133,16 +141,20 @@ DBWrapper::StartService() {
     opt.meta_.archive_conf_.SetCriterias(criterial);
 
     // create db root folder
-    Status status = CommonUtil::CreateDirectory(opt.meta_.path_);
-    if (!status.ok()) {
-        std::cerr << "ERROR! Failed to create database root path: " << opt.meta_.path_ << std::endl;
+    s = CommonUtil::CreateDirectory(opt.meta_.path_);
+    if (!s.ok()) {
+        std::cerr << "Error: Failed to create database primary path: " << path
+                  << ". Possible reason: db_config.primary_path is wrong in server_config.yaml or not available."
+                  << std::endl;
         kill(0, SIGUSR1);
     }
 
     for (auto& path : opt.meta_.slave_paths_) {
-        status = CommonUtil::CreateDirectory(path);
-        if (!status.ok()) {
-            std::cerr << "ERROR! Failed to create database slave path: " << path << std::endl;
+        s = CommonUtil::CreateDirectory(path);
+        if (!s.ok()) {
+            std::cerr << "Error: Failed to create database secondary path: " << path
+                      << ". Possible reason: db_config.secondary_path is wrong in server_config.yaml or not available."
+                      << std::endl;
             kill(0, SIGUSR1);
         }
     }
@@ -151,7 +163,9 @@ DBWrapper::StartService() {
     try {
         db_ = engine::DBFactory::Build(opt);
     } catch (std::exception& ex) {
-        std::cerr << "ERROR! Failed to open database: " << ex.what() << std::endl;
+        std::cerr << "Error: failed to open database: " << ex.what()
+                << ". Possible reason: the meta system does not work."
+                << std::endl;
         kill(0, SIGUSR1);
     }
 
@@ -161,7 +175,8 @@ DBWrapper::StartService() {
     std::string preload_tables;
     s = config.GetDBConfigPreloadTable(preload_tables);
     if (!s.ok()) {
-        return s;
+        std::cerr << s.ToString() << std::endl;
+        kill(0, SIGUSR1);
     }
 
     s = PreloadTables(preload_tables);
diff --git a/core/unittest/db/utils.cpp b/core/unittest/db/utils.cpp
index 8903ce14ea264ae253a0e45b81f065651732a85d..7cc2f287457a23887a3329d0bce955dd55363efe 100644
--- a/core/unittest/db/utils.cpp
+++ b/core/unittest/db/utils.cpp
@@ -68,7 +68,7 @@ static const char
                    "  blas_threshold: 20\n"
                    "\n"
                    "resource_config:\n"
-                   "  resource_pool:\n"
+                   "  search_resources:\n"
                    "    - gpu0\n"
                    "  index_build_device: gpu0          # GPU used for building index";
 
diff --git a/core/unittest/wrapper/utils.cpp b/core/unittest/wrapper/utils.cpp
index 6204ac0c05677832f039caa855c56d006c1c2675..b397a35d7c00d58938a02990603a2101ed5e82b4 100644
--- a/core/unittest/wrapper/utils.cpp
+++ b/core/unittest/wrapper/utils.cpp
@@ -58,7 +58,7 @@ static const char
                    "  blas_threshold: 20\n"
                    "\n"
                    "resource_config:\n"
-                   "  resource_pool:\n"
+                   "  search_resources:\n"
                    "    - gpu0\n"
                    "  index_build_device: gpu0          # GPU used for building index";