diff --git a/bootstrap.sh b/bootstrap.sh
index 17eeb35..0ba6b65 100644
--- a/bootstrap.sh
+++ b/bootstrap.sh
@@ -2,5 +2,6 @@
 
 . ./dev.sh
 
-go get -u github.com/siddontang/go-log/log
-go get -u github.com/siddontang/go-snappy/snappy
\ No newline at end of file
+go get github.com/siddontang/go-log/log
+go get github.com/siddontang/go-snappy/snappy
+go get github.com/siddontang/copier
\ No newline at end of file
diff --git a/etc/ledis.json b/etc/ledis.json
index 0d93e88..a683a81 100644
--- a/etc/ledis.json
+++ b/etc/ledis.json
@@ -2,13 +2,16 @@
     "addr": "127.0.0.1:6380",
     "data_dir": "/tmp/ledis_server",
     "db": {
-        "data_db" : {
             "compression": false,
             "block_size": 32768,
             "write_buffer_size": 67108864,
             "cache_size": 524288000,
             "max_open_files":1024         
-        }
+    },
+
+    "binlog" : {
+        "use" : false,
+        "max_open_files" : 1024
     },
 
     "access_log" : "access.log"
diff --git a/ledis/config.go b/ledis/config.go
new file mode 100644
index 0000000..fa4eede
--- /dev/null
+++ b/ledis/config.go
@@ -0,0 +1,19 @@
+package ledis
+
+type Config struct {
+	DataDir string `json:"data_dir"`
+
+	DB struct {
+		Compression     bool `json:"compression"`
+		BlockSize       int  `json:"block_size"`
+		WriteBufferSize int  `json:"write_buffer_size"`
+		CacheSize       int  `json:"cache_size"`
+		MaxOpenFiles    int  `json:"max_open_files"`
+	} `json:"db"`
+
+	BinLog struct {
+		Use         bool `json:"use"`
+		MaxFileSize int  `json:"max_file_size"`
+		MaxFileNum  int  `json:"max_file_num"`
+	} `json:"binlog"`
+}
diff --git a/ledis/ledis.go b/ledis/ledis.go
index cb83d01..80dcf29 100644
--- a/ledis/ledis.go
+++ b/ledis/ledis.go
@@ -3,6 +3,7 @@ package ledis
 import (
 	"encoding/json"
 	"fmt"
+	"github.com/siddontang/copier"
 	"github.com/siddontang/go-log/log"
 	"github.com/siddontang/ledisdb/leveldb"
 	"path"
@@ -10,18 +11,6 @@ import (
 	"time"
 )
 
-type Config struct {
-	DataDir string `json:"data_dir"`
-
-	//if you not set leveldb path, use data_dir/data
-	DataDB leveldb.Config `json:"data_db"`
-
-	UseBinLog bool `json:"use_bin_log"`
-
-	//if you not set bin log path, use data_dir/bin_log
-	BinLog BinLogConfig `json:"bin_log"`
-}
-
 type DB struct {
 	l *Ledis
 
@@ -60,16 +49,31 @@ func OpenWithJsonConfig(configJson json.RawMessage) (*Ledis, error) {
 	return Open(&cfg)
 }
 
+func openDB(cfg *Config) (*leveldb.DB, error) {
+	dbPath := path.Join(cfg.DataDir, "data")
+
+	dbCfg := new(leveldb.Config)
+	copier.Copy(dbCfg, &cfg.DB)
+	dbCfg.Path = dbPath
+
+	return leveldb.Open(dbCfg)
+}
+
+func openBinLog(cfg *Config) (*BinLog, error) {
+	binLogPath := path.Join(cfg.DataDir, "bin_log")
+	c := new(BinLogConfig)
+	copier.Copy(c, &cfg.BinLog)
+	c.Path = binLogPath
+
+	return NewBinLog(c)
+}
+
 func Open(cfg *Config) (*Ledis, error) {
 	if len(cfg.DataDir) == 0 {
 		return nil, fmt.Errorf("must set correct data_dir")
 	}
 
-	if len(cfg.DataDB.Path) == 0 {
-		cfg.DataDB.Path = path.Join(cfg.DataDir, "data")
-	}
-
-	ldb, err := leveldb.Open(&cfg.DataDB)
+	ldb, err := openDB(cfg)
 	if err != nil {
 		return nil, err
 	}
@@ -81,11 +85,8 @@ func Open(cfg *Config) (*Ledis, error) {
 
 	l.ldb = ldb
 
-	if cfg.UseBinLog {
-		if len(cfg.BinLog.Path) == 0 {
-			cfg.BinLog.Path = path.Join(cfg.DataDir, "bin_log")
-		}
-		l.binlog, err = NewBinLog(&cfg.BinLog)
+	if cfg.BinLog.Use {
+		l.binlog, err = openBinLog(cfg)
 		if err != nil {
 			return nil, err
 		}
diff --git a/ledis/ledis_test.go b/ledis/ledis_test.go
index aba2a62..07b285a 100644
--- a/ledis/ledis_test.go
+++ b/ledis/ledis_test.go
@@ -14,7 +14,7 @@ func getTestDB() *DB {
 		var d = []byte(`
             {
             	"data_dir" : "/tmp/test_ledis",
-                "data_db" : {
+                "db" : {
                     "compression":true,
                     "block_size" : 32768,
                     "write_buffer_size" : 2097152,
diff --git a/ledis/replication_test.go b/ledis/replication_test.go
index bc33f78..b5a939b 100644
--- a/ledis/replication_test.go
+++ b/ledis/replication_test.go
@@ -35,8 +35,8 @@ func TestReplication(t *testing.T) {
 	master, err = OpenWithJsonConfig([]byte(`
         {
             "data_dir" : "/tmp/test_repl/master",
-            "use_bin_log" : true,
-            "bin_log" : {
+            "binlog" : {
+            	"use" : true,
                 "max_file_size" : 50
             }
         } 
diff --git a/server/app.go b/server/app.go
index 9f155c1..756535c 100644
--- a/server/app.go
+++ b/server/app.go
@@ -2,6 +2,7 @@ package server
 
 import (
 	"fmt"
+	"github.com/siddontang/copier"
 	"github.com/siddontang/ledisdb/ledis"
 	"net"
 	"path"
@@ -30,10 +31,6 @@ func NewApp(cfg *Config) (*App, error) {
 		return nil, fmt.Errorf("must set data_dir first")
 	}
 
-	if len(cfg.DB.DataDir) == 0 {
-		cfg.DB.DataDir = cfg.DataDir
-	}
-
 	app := new(App)
 
 	app.quit = make(chan struct{})
@@ -66,7 +63,7 @@ func NewApp(cfg *Config) (*App, error) {
 		}
 	}
 
-	if app.ldb, err = ledis.Open(&cfg.DB); err != nil {
+	if app.ldb, err = openLedis(cfg); err != nil {
 		return nil, err
 	}
 
@@ -75,6 +72,19 @@ func NewApp(cfg *Config) (*App, error) {
 	return app, nil
 }
 
+func openLedis(cfg *Config) (*ledis.Ledis, error) {
+	c := new(ledis.Config)
+
+	c.DataDir = cfg.DataDir
+
+	copier.Copy(&c.DB, &cfg.DB)
+	copier.Copy(&c.BinLog, &cfg.BinLog)
+
+	println("max open files", c.DB.MaxOpenFiles)
+
+	return ledis.Open(c)
+}
+
 func (app *App) Close() {
 	if app.closed {
 		return
diff --git a/server/app_test.go b/server/app_test.go
index b4db346..2b73ab5 100644
--- a/server/app_test.go
+++ b/server/app_test.go
@@ -34,13 +34,12 @@ func startTestApp() {
             {
                 "data_dir" : "/tmp/testdb",
                 "addr" : "127.0.0.1:16380",
-                "db" : {
-                    "data_db" : {
-                        "compression":true,
-                        "block_size" : 32768,
-                        "write_buffer_size" : 2097152,
-                        "cache_size" : 20971520
-                    }
+                "db" : {        
+                    "compression":true,
+                    "block_size" : 32768,
+                    "write_buffer_size" : 2097152,
+                    "cache_size" : 20971520,
+                    "max_open_files" : 1024
                 }    
             }
             `)
diff --git a/server/cmd_replication_test.go b/server/cmd_replication_test.go
index 290d94b..dce4b6f 100644
--- a/server/cmd_replication_test.go
+++ b/server/cmd_replication_test.go
@@ -32,7 +32,7 @@ func TestReplication(t *testing.T) {
 	masterCfg := new(Config)
 	masterCfg.DataDir = fmt.Sprintf("%s/master", data_dir)
 	masterCfg.Addr = "127.0.0.1:11182"
-	masterCfg.DB.UseBinLog = true
+	masterCfg.BinLog.Use = true
 
 	var master *App
 	var slave *App
diff --git a/server/config.go b/server/config.go
index 89aba2c..64243e8 100644
--- a/server/config.go
+++ b/server/config.go
@@ -2,7 +2,6 @@ package server
 
 import (
 	"encoding/json"
-	"github.com/siddontang/ledisdb/ledis"
 	"io/ioutil"
 )
 
@@ -11,8 +10,19 @@ type Config struct {
 
 	DataDir string `json:"data_dir"`
 
-	//if you not set db path, use data_dir
-	DB ledis.Config `json:"db"`
+	DB struct {
+		Compression     bool `json:"compression"`
+		BlockSize       int  `json:"block_size"`
+		WriteBufferSize int  `json:"write_buffer_size"`
+		CacheSize       int  `json:"cache_size"`
+		MaxOpenFiles    int  `json:"max_open_files"`
+	} `json:"db"`
+
+	BinLog struct {
+		Use         bool `json:"use"`
+		MaxFileSize int  `json:"max_file_size"`
+		MaxFileNum  int  `json:"max_file_num"`
+	} `json:"binlog"`
 
 	//set slaveof to enable replication from master
 	//empty, no replication