diff --git a/src/manager/UpstreamManager.h b/src/manager/UpstreamManager.h
index fa739f59..fbbed67e 100644
--- a/src/manager/UpstreamManager.h
+++ b/src/manager/UpstreamManager.h
@@ -46,7 +46,7 @@
  * - Additional, we support Main-backup & Group for server and working well in any mode.
  *
  * @code{.cc}
-	upstream_create_weighted_random("abc.sogou", true);           //UPSTREAM_WIGHTED_RANDOM
+	upstream_create_weighted_random("abc.sogou", true);           //UPSTREAM_WEIGHTED_RANDOM
 	upstream_add_server("abc.sogou", "192.168.2.100:8081");       //weight=1, max_fails=200
 	upstream_add_server("abc.sogou", "192.168.2.100:9090");       //weight=1, max_fails=200
 	AddressParams params = ADDRESS_PARAMS_DEFAULT;
@@ -136,7 +136,7 @@ public:
 	 * @note
 	 */
 	static int upstream_create_vnswrr(const std::string& name);
-	
+
 	/**
 	 * @brief      Delete one upstream
 	 * @param[in]  name             upstream name
diff --git a/src/nameservice/UpstreamPolicies.cc b/src/nameservice/UpstreamPolicies.cc
index a401e47f..707b507e 100644
--- a/src/nameservice/UpstreamPolicies.cc
+++ b/src/nameservice/UpstreamPolicies.cc
@@ -169,11 +169,6 @@ bool UPSGroupPolicy::select(const ParsedURI& uri, WFNSTracing *tracing,
 	}
 
 	this->check_breaker();
-	if (this->nalives == 0)
-	{
-		this->rwlock.unlock();
-		return false;
-	}
 
 	// select_addr == NULL will only happened in consistent_hash
 	EndpointAddress *select_addr = this->first_strategy(uri, tracing);
@@ -201,17 +196,17 @@ bool UPSGroupPolicy::select(const ParsedURI& uri, WFNSTracing *tracing,
 }
 
 /*
- * flag true : return an available one. If not exists, return NULL.
- *      false: means addr maybe group-alive.
- *      	   If addr is not available, get one from addr->group.
+ * addr_failed true: return an available one. If not exists, return NULL.
+ * 			  false: means addr maybe group-alive.
+ * 					 If addr is not available, get one from addr->group.
  */
 EndpointAddress *UPSGroupPolicy::check_and_get(EndpointAddress *addr,
-											   bool flag,
+											   bool addr_failed,
 											   WFNSTracing *tracing)
 {
 	UPSAddrParams *params = static_cast<UPSAddrParams *>(addr->params);
 
-	if (flag == true) // && addr->fail_count >= addr->params->max_fails
+	if (addr_failed) // means fail_count >= max_fails
 	{
 		if (params->group_id == -1)
 			return NULL;
@@ -404,7 +399,8 @@ int UPSGroupPolicy::remove_server_locked(const std::string& address)
 	return ret;
 }
 
-EndpointAddress *UPSGroupPolicy::consistent_hash_with_group(unsigned int hash)
+EndpointAddress *UPSGroupPolicy::consistent_hash_with_group(unsigned int hash,
+															WFNSTracing *tracing)
 {
 	const UPSAddrParams *params;
 	EndpointAddress *addr = NULL;
@@ -434,7 +430,7 @@ EndpointAddress *UPSGroupPolicy::consistent_hash_with_group(unsigned int hash)
 	if (!addr)
 		return NULL;
 
-	return this->check_and_get(addr, false, NULL);
+	return this->check_and_get(addr, false, tracing);
 }
 
 void UPSWeightedRandomPolicy::add_server_locked(EndpointAddress *addr)
@@ -584,7 +580,7 @@ EndpointAddress *UPSVNSWRRPolicy::first_strategy(const ParsedURI& uri,
 
 		break;
 	}
-	this->cur_idx = idx;
+	this->cur_idx = idx + 1;
 	return this->servers[idx];
 }
 
@@ -643,7 +639,7 @@ EndpointAddress *UPSConsistentHashPolicy::first_strategy(const ParsedURI& uri,
 										uri.path ? uri.path : "",
 										uri.query ? uri.query : "",
 										uri.fragment ? uri.fragment : "");
-	return this->consistent_hash_with_group(hash_value);
+	return this->consistent_hash_with_group(hash_value, tracing);
 }
 
 EndpointAddress *UPSManualPolicy::first_strategy(const ParsedURI& uri,
@@ -666,6 +662,6 @@ EndpointAddress *UPSManualPolicy::another_strategy(const ParsedURI& uri,
 										uri.path ? uri.path : "",
 										uri.query ? uri.query : "",
 										uri.fragment ? uri.fragment : "");
-	return this->consistent_hash_with_group(hash_value);
+	return this->consistent_hash_with_group(hash_value, tracing);
 }
 
diff --git a/src/nameservice/UpstreamPolicies.h b/src/nameservice/UpstreamPolicies.h
index 4a82ba3a..48046c01 100644
--- a/src/nameservice/UpstreamPolicies.h
+++ b/src/nameservice/UpstreamPolicies.h
@@ -74,9 +74,10 @@ protected:
 	virtual void add_server_locked(EndpointAddress *addr);
 	virtual int remove_server_locked(const std::string& address);
 
-	EndpointAddress *consistent_hash_with_group(unsigned int hash);
+	EndpointAddress *consistent_hash_with_group(unsigned int hash,
+												WFNSTracing *tracing);
 	EndpointAddress *check_and_get(EndpointAddress *addr,
-								   bool flag, WFNSTracing *tracing);
+								   bool addr_failed, WFNSTracing *tracing);
 
 	bool is_alive(const EndpointAddress *addr) const;
 };
diff --git a/src/nameservice/WFServiceGovernance.cc b/src/nameservice/WFServiceGovernance.cc
index ba182e2f..71d2dc8d 100644
--- a/src/nameservice/WFServiceGovernance.cc
+++ b/src/nameservice/WFServiceGovernance.cc
@@ -164,10 +164,6 @@ void WFServiceGovernance::tracing_deleter(void *data)
 bool WFServiceGovernance::in_select_history(WFNSTracing *tracing,
 											EndpointAddress *addr)
 {
-	/* 'tracing' is NULL in consistent hash. */
-	if (!tracing)
-		return false;
-
 	struct TracingData *tracing_data = (struct TracingData *)tracing->data;
 
 	if (!tracing_data)