diff --git a/client/client_func.c b/client/client_func.c
index 99ab50f..43b1d3d 100644
--- a/client/client_func.c
+++ b/client/client_func.c
@@ -241,7 +241,7 @@ static int fdfs_get_params_from_tracker(bool *use_storage_id)
 
 	continue_flag = false;
 	if ((result=fdfs_get_ini_context_from_tracker(&g_tracker_group,
-		&iniContext, &continue_flag, false, NULL)) != 0)
+                    &iniContext, &continue_flag)) != 0)
     {
         return result;
     }
diff --git a/conf/storage.conf b/conf/storage.conf
index 273b1f7..3b2691c 100644
--- a/conf/storage.conf
+++ b/conf/storage.conf
@@ -28,6 +28,14 @@ client_bind = true
 # the storage server port
 port = 23000
 
+# the address family of service, value list:
+##  IPv4: IPv4 stack
+##  IPv6: IPv6 stack
+##  auto: auto detect, IPv4 first, then IPv6
+##  both: IPv4 and IPv6 dual stacks
+# default value is auto
+address_family = auto
+
 # connect timeout in seconds
 # default value is 30
 # Note: in the intranet network (LAN), 2 seconds is enough.
diff --git a/conf/tracker.conf b/conf/tracker.conf
index 8280838..84c830f 100644
--- a/conf/tracker.conf
+++ b/conf/tracker.conf
@@ -15,6 +15,14 @@ bind_addr =
 # the tracker server port
 port = 22122
 
+# the address family of service, value list:
+##  IPv4: IPv4 stack
+##  IPv6: IPv6 stack
+##  auto: auto detect, IPv4 first, then IPv6
+##  both: IPv4 and IPv6 dual stacks
+# default value is auto
+address_family = auto
+
 # connect timeout in seconds
 # default value is 30
 # Note: in the intranet network (LAN), 2 seconds is enough.
diff --git a/storage/fdfs_storaged.c b/storage/fdfs_storaged.c
index e0ab1a7..643d4a7 100644
--- a/storage/fdfs_storaged.c
+++ b/storage/fdfs_storaged.c
@@ -351,14 +351,30 @@ static void sigAlarmHandler(int sig)
 	logDebug("file: "__FILE__", line: %d, " \
 		"signal server to quit...", __LINE__);
 
-	if (*SF_G_INNER_BIND_ADDR != '\0')
-	{
-		strcpy(server.ip_addr, SF_G_INNER_BIND_ADDR);
-	}
-	else
-	{
-		strcpy(server.ip_addr, "127.0.0.1");
-	}
+    if (SF_G_IPV4_ENABLED)
+    {
+        server.af = AF_INET;
+        if (*SF_G_INNER_BIND_ADDR4 != '\0')
+        {
+            strcpy(server.ip_addr, SF_G_INNER_BIND_ADDR4);
+        }
+        else
+        {
+            strcpy(server.ip_addr, LOCAL_LOOPBACK_IPv4);
+        }
+    }
+    else
+    {
+        server.af = AF_INET6;
+        if (*SF_G_INNER_BIND_ADDR6 != '\0')
+        {
+            strcpy(server.ip_addr, SF_G_INNER_BIND_ADDR6);
+        }
+        else
+        {
+            strcpy(server.ip_addr, LOCAL_LOOPBACK_IPv6);
+        }
+    }
 	server.port = SF_G_INNER_PORT;
 	server.sock = -1;
 
diff --git a/storage/storage_dump.c b/storage/storage_dump.c
index 8be021b..dc18e7a 100644
--- a/storage/storage_dump.c
+++ b/storage/storage_dump.c
@@ -93,7 +93,8 @@ static int fdfs_dump_global_vars(char *buff, const int buffSize)
 		"g_check_file_duplicate=%d\n"
 		"g_key_namespace=%s\n"
 		"g_namespace_len=%d\n"
-		"SF_G_INNER_BIND_ADDR=%s\n"
+		"bind_addr_ipv4=%s\n"
+		"bind_addr_ipv6=%s\n"
 		"g_client_bind_addr=%d\n"
 		"g_storage_ip_changed_auto_adjust=%d\n"
 		"g_thread_kill_done=%d\n"
@@ -188,7 +189,8 @@ static int fdfs_dump_global_vars(char *buff, const int buffSize)
 		, g_check_file_duplicate
 		, g_key_namespace
 		, g_namespace_len
-		, SF_G_INNER_BIND_ADDR
+		, SF_G_INNER_BIND_ADDR4
+		, SF_G_INNER_BIND_ADDR6
 		, g_client_bind_addr
 		, g_storage_ip_changed_auto_adjust
 		, g_thread_kill_done
diff --git a/storage/storage_ip_changed_dealer.c b/storage/storage_ip_changed_dealer.c
index 5e58505..a8ac10f 100644
--- a/storage/storage_ip_changed_dealer.c
+++ b/storage/storage_ip_changed_dealer.c
@@ -146,7 +146,8 @@ int storage_get_my_tracker_client_ip()
 		for (i=0; i < 3; i++)
 		{
             conn = tracker_connect_server_no_pool_ex(pTServer,
-                    g_client_bind_addr ? SF_G_INNER_BIND_ADDR : NULL,
+                    (g_client_bind_addr ? SF_G_INNER_BIND_ADDR4 : NULL),
+                    (g_client_bind_addr ? SF_G_INNER_BIND_ADDR6 : NULL),
                     &result, false);
             if (conn != NULL)
             {
@@ -234,7 +235,8 @@ static int storage_report_storage_ip_addr()
 		for (i=0; i < 3; i++)
 		{
             conn = tracker_connect_server_no_pool_ex(pTServer,
-                    g_client_bind_addr ? SF_G_INNER_BIND_ADDR : NULL,
+                    (g_client_bind_addr ? SF_G_INNER_BIND_ADDR4 : NULL),
+                    (g_client_bind_addr ? SF_G_INNER_BIND_ADDR6 : NULL),
                     &result, false);
             if (conn != NULL)
             {
@@ -304,7 +306,8 @@ int storage_changelog_req()
 		for (i=0; i < 3; i++)
 		{
             conn = tracker_connect_server_no_pool_ex(pTServer,
-                    g_client_bind_addr ? SF_G_INNER_BIND_ADDR : NULL,
+                    (g_client_bind_addr ? SF_G_INNER_BIND_ADDR4 : NULL),
+                    (g_client_bind_addr ? SF_G_INNER_BIND_ADDR6 : NULL),
                     &result, false);
             if (conn != NULL)
             {
diff --git a/storage/storage_param_getter.c b/storage/storage_param_getter.c
index e59a3b0..d9f72c8 100644
--- a/storage/storage_param_getter.c
+++ b/storage/storage_param_getter.c
@@ -74,9 +74,10 @@ int storage_get_params_from_tracker()
 	char reserved_space_str[32];
 	char *pIdType;
 
-	if ((result=fdfs_get_ini_context_from_tracker(&g_tracker_group,
-		&iniContext, (bool * volatile)&SF_G_CONTINUE_FLAG,
-		g_client_bind_addr, SF_G_INNER_BIND_ADDR)) != 0)
+	if ((result=fdfs_get_ini_context_from_tracker_ex(&g_tracker_group,
+                    &iniContext, (bool * volatile)&SF_G_CONTINUE_FLAG,
+                    g_client_bind_addr, SF_G_INNER_BIND_ADDR4,
+                    SF_G_INNER_BIND_ADDR6)) != 0)
 	{
 		return result;
 	}
diff --git a/storage/storage_sync.c b/storage/storage_sync.c
index 26a275b..2c468ff 100644
--- a/storage/storage_sync.c
+++ b/storage/storage_sync.c
@@ -2050,7 +2050,9 @@ int storage_report_storage_status(const char *storage_id, \
 		for (i=0; i < 3; i++)
 		{
             conn = tracker_connect_server_no_pool_ex(pTServer,
-                    g_client_bind_addr ? SF_G_INNER_BIND_ADDR : NULL, &result, false);
+                    (g_client_bind_addr ? SF_G_INNER_BIND_ADDR4 : NULL),
+                    (g_client_bind_addr ? SF_G_INNER_BIND_ADDR6 : NULL),
+                    &result, false);
             if (conn != NULL)
             {
 				break;
@@ -2146,7 +2148,9 @@ static int storage_reader_sync_init_req(StorageBinLogReader *pReader)
 		while (SF_G_CONTINUE_FLAG)
 		{
             conn = tracker_connect_server_no_pool_ex(pTServer,
-                    g_client_bind_addr ? SF_G_INNER_BIND_ADDR : NULL, &result, true);
+                    (g_client_bind_addr ? SF_G_INNER_BIND_ADDR4 : NULL),
+                    (g_client_bind_addr ? SF_G_INNER_BIND_ADDR6 : NULL),
+                    &result, true);
             if (conn != NULL)
             {
 				break;
diff --git a/storage/storage_sync_func.c b/storage/storage_sync_func.c
index b679281..08fb4e1 100644
--- a/storage/storage_sync_func.c
+++ b/storage/storage_sync_func.c
@@ -39,6 +39,7 @@ void storage_sync_connect_storage_server_ex(const FDFSStorageBrief *pStorage,
     int i;
     FDFSMultiIP ip_addrs;
     FDFSMultiIP *multi_ip;
+    const char *bind_addr;
 
     multi_ip = NULL;
     if (g_use_storage_id)
@@ -83,9 +84,17 @@ void storage_sync_connect_storage_server_ex(const FDFSStorageBrief *pStorage,
         for (i=0; i<ip_addrs.count; i++)
         {
             strcpy(conn->ip_addr, ip_addrs.ips[i].address);
+            if (g_client_bind_addr)
+            {
+                bind_addr = is_ipv6_addr(conn->ip_addr) ?
+                    SF_G_INNER_BIND_ADDR6 : SF_G_INNER_BIND_ADDR4;
+            }
+            else
+            {
+                bind_addr = NULL;
+            }
             conn->sock = socketCreateExAuto(conn->ip_addr,
-                    O_NONBLOCK, g_client_bind_addr ?
-                    SF_G_INNER_BIND_ADDR : NULL, &result);
+                    O_NONBLOCK, bind_addr, &result);
             if (conn->sock < 0)
             {
                 logCrit("file: "__FILE__", line: %d, "
diff --git a/storage/tracker_client_thread.c b/storage/tracker_client_thread.c
index 4f05434..c034b41 100644
--- a/storage/tracker_client_thread.c
+++ b/storage/tracker_client_thread.c
@@ -257,9 +257,10 @@ static void *tracker_report_thread_entrance(void *arg)
         }
 
         conn = tracker_connect_server_no_pool_ex(pTrackerServer,
-                g_client_bind_addr ? SF_G_INNER_BIND_ADDR : NULL,
+                (g_client_bind_addr ? SF_G_INNER_BIND_ADDR4 : NULL),
+                (g_client_bind_addr ? SF_G_INNER_BIND_ADDR6 : NULL),
                 &result, false);
-		if (conn == NULL)
+        if (conn == NULL)
 		{
 			if (previousCode != result)
 			{
diff --git a/test/test_types.h b/test/test_types.h
index 4ff6fa2..2dfb2dc 100644
--- a/test/test_types.h
+++ b/test/test_types.h
@@ -13,7 +13,6 @@
 #define FILENAME_FILE_ID     "file_id"
 #define FILENAME_FAIL        "fail"
 
-#define IP_ADDRESS_SIZE		16
 #define SRAND_SEED		1225420780
 
 #define TIME_SUB_MS(tv1, tv2)  ((tv1.tv_sec - tv2.tv_sec) * 1000 + (tv1.tv_usec - tv2.tv_usec) / 1000)
diff --git a/tracker/fdfs_trackerd.c b/tracker/fdfs_trackerd.c
index 16b55c8..688a7e4 100644
--- a/tracker/fdfs_trackerd.c
+++ b/tracker/fdfs_trackerd.c
@@ -423,14 +423,30 @@ static void sigAlarmHandler(int sig)
 	logDebug("file: "__FILE__", line: %d, " \
 		"signal server to quit...", __LINE__);
 
-	if (*g_sf_context.inner_bind_addr != '\0')
-	{
-		strcpy(server.ip_addr, g_sf_context.inner_bind_addr);
-	}
-	else
-	{
-		strcpy(server.ip_addr, "127.0.0.1");
-	}
+    if (SF_G_IPV4_ENABLED)
+    {
+        server.af = AF_INET;
+        if (*SF_G_INNER_BIND_ADDR4 != '\0')
+        {
+            strcpy(server.ip_addr, SF_G_INNER_BIND_ADDR4);
+        }
+        else
+        {
+            strcpy(server.ip_addr, LOCAL_LOOPBACK_IPv4);
+        }
+    }
+    else
+    {
+        server.af = AF_INET6;
+        if (*SF_G_INNER_BIND_ADDR6 != '\0')
+        {
+            strcpy(server.ip_addr, SF_G_INNER_BIND_ADDR6);
+        }
+        else
+        {
+            strcpy(server.ip_addr, LOCAL_LOOPBACK_IPv6);
+        }
+    }
 	server.port = SF_G_INNER_PORT;
 	server.sock = -1;
 
diff --git a/tracker/tracker_proto.c b/tracker/tracker_proto.c
index 8208563..d7586c2 100644
--- a/tracker/tracker_proto.c
+++ b/tracker/tracker_proto.c
@@ -488,7 +488,8 @@ ConnectionInfo *tracker_connect_server_ex(TrackerServerInfo *pServerInfo,
 }
 
 ConnectionInfo *tracker_connect_server_no_pool_ex(TrackerServerInfo *pServerInfo,
-        const char *bind_addr, int *err_no, const bool log_connect_error)
+        const char *bind_addr4, const char *bind_addr6, int *err_no,
+        const bool log_connect_error)
 {
 	ConnectionInfo *conn;
 	ConnectionInfo *end;
@@ -500,12 +501,12 @@ ConnectionInfo *tracker_connect_server_no_pool_ex(TrackerServerInfo *pServerInfo
 		return pServerInfo->connections + pServerInfo->index;
 	}
 
-	*err_no = conn_pool_connect_server_ex(pServerInfo->connections
-            + pServerInfo->index, SF_G_CONNECT_TIMEOUT * 1000,
-            bind_addr, log_connect_error);
+    conn = pServerInfo->connections + pServerInfo->index;
+	*err_no = conn_pool_connect_server_ex(conn, SF_G_CONNECT_TIMEOUT * 1000,
+            conn->af == AF_INET ? bind_addr4 : bind_addr6, log_connect_error);
     if (*err_no == 0)
     {
-		return pServerInfo->connections + pServerInfo->index;
+        return conn;
     }
 
     if (pServerInfo->count == 1)
@@ -520,11 +521,12 @@ ConnectionInfo *tracker_connect_server_no_pool_ex(TrackerServerInfo *pServerInfo
         if (current_index != pServerInfo->index)
         {
             if ((*err_no=conn_pool_connect_server_ex(conn,
-                            SF_G_CONNECT_TIMEOUT * 1000, bind_addr,
-                            log_connect_error)) == 0)
+                            SF_G_CONNECT_TIMEOUT * 1000,
+                            conn->af == AF_INET ? bind_addr4 :
+                            bind_addr6, log_connect_error)) == 0)
             {
                 pServerInfo->index = current_index;
-                return pServerInfo->connections + pServerInfo->index;
+                return conn;
             }
         }
     }
@@ -633,9 +635,10 @@ static int fdfs_do_parameter_req(ConnectionInfo *pTrackerServer, \
 	return 0;
 }
 
-int fdfs_get_ini_context_from_tracker(TrackerServerGroup *pTrackerGroup, \
-		IniContext *iniContext, bool * volatile continue_flag, \
-		const bool client_bind_addr, const char *bind_addr)
+int fdfs_get_ini_context_from_tracker_ex(TrackerServerGroup *pTrackerGroup,
+                IniContext *iniContext, bool * volatile continue_flag,
+                const bool client_bind_addr, const char *bind_addr4,
+                const char *bind_addr6)
 {
     ConnectionInfo *conn;
 	TrackerServerInfo *pGlobalServer;
@@ -664,7 +667,14 @@ int fdfs_get_ini_context_from_tracker(TrackerServerGroup *pTrackerGroup, \
 
     if (!client_bind_addr)
     {
-        bind_addr = NULL;
+        if (bind_addr4 != NULL)
+        {
+            bind_addr4 = NULL;
+        }
+        if (bind_addr6 != NULL)
+        {
+            bind_addr6 = NULL;
+        }
     }
 
 	do
@@ -678,7 +688,7 @@ int fdfs_get_ini_context_from_tracker(TrackerServerGroup *pTrackerGroup, \
             for (i=0; i < 3; i++)
             {
                 conn = tracker_connect_server_no_pool_ex(pTServer,
-                        bind_addr, &result, false);
+                        bind_addr4, bind_addr6, &result, false);
                 if (conn != NULL)
                 {
                     break;
diff --git a/tracker/tracker_proto.h b/tracker/tracker_proto.h
index 5383848..19c8674 100644
--- a/tracker/tracker_proto.h
+++ b/tracker/tracker_proto.h
@@ -240,13 +240,15 @@ ConnectionInfo *tracker_connect_server_ex(TrackerServerInfo *pServerInfo,
 * connect to the tracker server directly without connection pool
 * params:
 *	pTrackerServer: tracker server
-*   bind_ipaddr: the ip address to bind, NULL or empty for any
+*   bind_addr4: the ipv4 address to bind, NULL or empty for any
+*   bind_addr6: the ipv6 address to bind, NULL or empty for any
 *	err_no: return the error no
 *   log_connect_error: if log error info when connect fail
 * return: ConnectionInfo pointer for success, NULL for fail
 **/
 ConnectionInfo *tracker_connect_server_no_pool_ex(TrackerServerInfo *pServerInfo,
-        const char *bind_addr, int *err_no, const bool log_connect_error);
+        const char *bind_addr4, const char *bind_addr6, int *err_no,
+        const bool log_connect_error);
 
 /**
 * connect to the tracker server directly without connection pool
@@ -258,9 +260,10 @@ ConnectionInfo *tracker_connect_server_no_pool_ex(TrackerServerInfo *pServerInfo
 static inline ConnectionInfo *tracker_connect_server_no_pool(
         TrackerServerInfo *pServerInfo, int *err_no)
 {
-    const char *bind_addr = NULL;
+    const char *bind_addr4 = NULL;
+    const char *bind_addr6 = NULL;
     return tracker_connect_server_no_pool_ex(pServerInfo,
-            bind_addr, err_no, true);
+            bind_addr4, bind_addr6, err_no, true);
 }
 
 #define tracker_close_connection(pTrackerServer) \
@@ -316,15 +319,21 @@ int fdfs_deal_no_body_cmd_ex(const char *ip_addr, const int port, const int cmd)
 		fdfs_split_metadata_ex(meta_buff, FDFS_RECORD_SEPERATOR, \
 		FDFS_FIELD_SEPERATOR, meta_count, err_no)
 
-char *fdfs_pack_metadata(const FDFSMetaData *meta_list, const int meta_count, \
+char *fdfs_pack_metadata(const FDFSMetaData *meta_list, const int meta_count,
 			char *meta_buff, int *buff_bytes);
-FDFSMetaData *fdfs_split_metadata_ex(char *meta_buff, \
-		const char recordSeperator, const char filedSeperator, \
+FDFSMetaData *fdfs_split_metadata_ex(char *meta_buff,
+		const char recordSeperator, const char filedSeperator,
 		int *meta_count, int *err_no);
 
-int fdfs_get_ini_context_from_tracker(TrackerServerGroup *pTrackerGroup, \
-                IniContext *iniContext, bool * volatile continue_flag, \
-                const bool client_bind_addr, const char *bind_addr);
+int fdfs_get_ini_context_from_tracker_ex(TrackerServerGroup *pTrackerGroup,
+                IniContext *iniContext, bool * volatile continue_flag,
+                const bool client_bind_addr, const char *bind_addr4,
+                const char *bind_addr6);
+
+#define fdfs_get_ini_context_from_tracker(pTrackerGroup, \
+        iniContext, continue_flag) \
+        fdfs_get_ini_context_from_tracker_ex(pTrackerGroup, \
+        iniContext, continue_flag, false, NULL, NULL)
 
 int fdfs_get_tracker_status(TrackerServerInfo *pTrackerServer,
 		TrackerRunningStatus *pStatus);