diff --git a/Makefile b/Makefile
index 14c07fa86..bbca92151 100644
--- a/Makefile
+++ b/Makefile
@@ -5,7 +5,7 @@ SOURCE_DIR = ./go/weed/
 
 all: build
 
-.PHONY : clean deps build linux
+.PHONY : clean deps build linux vet
 
 clean:
 	go clean -i $(GO_FLAGS) $(SOURCE_DIR)
@@ -17,6 +17,9 @@ deps:
 fmt:
 	gofmt -w -s ./go/
 
+vet:
+	go vet ./go/...
+
 build: deps fmt
 	go build $(GO_FLAGS) -o $(BINARY) $(SOURCE_DIR)
 
diff --git a/go/operation/data_struts.go b/go/operation/data_struts.go
deleted file mode 100644
index bfc53aa50..000000000
--- a/go/operation/data_struts.go
+++ /dev/null
@@ -1,7 +0,0 @@
-package operation
-
-type JoinResult struct {
-	VolumeSizeLimit uint64 `json:"VolumeSizeLimit,omitempty"`
-	SecretKey       string `json:"secretKey,omitempty"`
-	Error           string `json:"error,omitempty"`
-}
diff --git a/go/operation/system_message.pb.go b/go/operation/system_message.pb.go
deleted file mode 100644
index 2574b2af6..000000000
--- a/go/operation/system_message.pb.go
+++ /dev/null
@@ -1,278 +0,0 @@
-// Code generated by protoc-gen-go.
-// source: system_message.proto
-// DO NOT EDIT!
-
-/*
-Package operation is a generated protocol buffer package.
-
-It is generated from these files:
-	system_message.proto
-
-It has these top-level messages:
-	VolumeInformationMessage
-	JoinMessage
-	CollectionSetting
-	GlobalSetting
-	JoinResponse
-*/
-package operation
-
-import proto "github.com/golang/protobuf/proto"
-import math "math"
-
-// Reference imports to suppress errors if they are not otherwise used.
-var _ = proto.Marshal
-var _ = math.Inf
-
-type VolumeInformationMessage struct {
-	Id               *uint32 `protobuf:"varint,1,req,name=id" json:"id,omitempty"`
-	Size             *uint64 `protobuf:"varint,2,req,name=size" json:"size,omitempty"`
-	Collection       *string `protobuf:"bytes,3,opt,name=collection" json:"collection,omitempty"`
-	FileCount        *uint64 `protobuf:"varint,4,req,name=file_count" json:"file_count,omitempty"`
-	DeleteCount      *uint64 `protobuf:"varint,5,req,name=delete_count" json:"delete_count,omitempty"`
-	DeletedByteCount *uint64 `protobuf:"varint,6,req,name=deleted_byte_count" json:"deleted_byte_count,omitempty"`
-	ReadOnly         *bool   `protobuf:"varint,7,opt,name=read_only" json:"read_only,omitempty"`
-	ReplicaPlacement *uint32 `protobuf:"varint,8,opt,name=replica_placement" json:"replica_placement,omitempty"`
-	Version          *uint32 `protobuf:"varint,9,opt,name=version,def=2" json:"version,omitempty"`
-	Ttl              *uint32 `protobuf:"varint,10,opt,name=ttl" json:"ttl,omitempty"`
-	XXX_unrecognized []byte  `json:"-"`
-}
-
-func (m *VolumeInformationMessage) Reset()         { *m = VolumeInformationMessage{} }
-func (m *VolumeInformationMessage) String() string { return proto.CompactTextString(m) }
-func (*VolumeInformationMessage) ProtoMessage()    {}
-
-const Default_VolumeInformationMessage_Version uint32 = 2
-
-func (m *VolumeInformationMessage) GetId() uint32 {
-	if m != nil && m.Id != nil {
-		return *m.Id
-	}
-	return 0
-}
-
-func (m *VolumeInformationMessage) GetSize() uint64 {
-	if m != nil && m.Size != nil {
-		return *m.Size
-	}
-	return 0
-}
-
-func (m *VolumeInformationMessage) GetCollection() string {
-	if m != nil && m.Collection != nil {
-		return *m.Collection
-	}
-	return ""
-}
-
-func (m *VolumeInformationMessage) GetFileCount() uint64 {
-	if m != nil && m.FileCount != nil {
-		return *m.FileCount
-	}
-	return 0
-}
-
-func (m *VolumeInformationMessage) GetDeleteCount() uint64 {
-	if m != nil && m.DeleteCount != nil {
-		return *m.DeleteCount
-	}
-	return 0
-}
-
-func (m *VolumeInformationMessage) GetDeletedByteCount() uint64 {
-	if m != nil && m.DeletedByteCount != nil {
-		return *m.DeletedByteCount
-	}
-	return 0
-}
-
-func (m *VolumeInformationMessage) GetReadOnly() bool {
-	if m != nil && m.ReadOnly != nil {
-		return *m.ReadOnly
-	}
-	return false
-}
-
-func (m *VolumeInformationMessage) GetReplicaPlacement() uint32 {
-	if m != nil && m.ReplicaPlacement != nil {
-		return *m.ReplicaPlacement
-	}
-	return 0
-}
-
-func (m *VolumeInformationMessage) GetVersion() uint32 {
-	if m != nil && m.Version != nil {
-		return *m.Version
-	}
-	return Default_VolumeInformationMessage_Version
-}
-
-func (m *VolumeInformationMessage) GetTtl() uint32 {
-	if m != nil && m.Ttl != nil {
-		return *m.Ttl
-	}
-	return 0
-}
-
-type JoinMessage struct {
-	IsInit           *bool                       `protobuf:"varint,1,opt,name=is_init" json:"is_init,omitempty"`
-	Ip               *string                     `protobuf:"bytes,2,req,name=ip" json:"ip,omitempty"`
-	Port             *uint32                     `protobuf:"varint,3,req,name=port" json:"port,omitempty"`
-	PublicUrl        *string                     `protobuf:"bytes,4,opt,name=public_url" json:"public_url,omitempty"`
-	MaxVolumeCount   *uint32                     `protobuf:"varint,5,req,name=max_volume_count" json:"max_volume_count,omitempty"`
-	MaxFileKey       *uint64                     `protobuf:"varint,6,req,name=max_file_key" json:"max_file_key,omitempty"`
-	DataCenter       *string                     `protobuf:"bytes,7,opt,name=data_center" json:"data_center,omitempty"`
-	Rack             *string                     `protobuf:"bytes,8,opt,name=rack" json:"rack,omitempty"`
-	Volumes          []*VolumeInformationMessage `protobuf:"bytes,9,rep,name=volumes" json:"volumes,omitempty"`
-	AdminPort        *uint32                     `protobuf:"varint,10,opt,name=admin_port" json:"admin_port,omitempty"`
-	XXX_unrecognized []byte                      `json:"-"`
-}
-
-func (m *JoinMessage) Reset()         { *m = JoinMessage{} }
-func (m *JoinMessage) String() string { return proto.CompactTextString(m) }
-func (*JoinMessage) ProtoMessage()    {}
-
-func (m *JoinMessage) GetIsInit() bool {
-	if m != nil && m.IsInit != nil {
-		return *m.IsInit
-	}
-	return false
-}
-
-func (m *JoinMessage) GetIp() string {
-	if m != nil && m.Ip != nil {
-		return *m.Ip
-	}
-	return ""
-}
-
-func (m *JoinMessage) GetPort() uint32 {
-	if m != nil && m.Port != nil {
-		return *m.Port
-	}
-	return 0
-}
-
-func (m *JoinMessage) GetPublicUrl() string {
-	if m != nil && m.PublicUrl != nil {
-		return *m.PublicUrl
-	}
-	return ""
-}
-
-func (m *JoinMessage) GetMaxVolumeCount() uint32 {
-	if m != nil && m.MaxVolumeCount != nil {
-		return *m.MaxVolumeCount
-	}
-	return 0
-}
-
-func (m *JoinMessage) GetMaxFileKey() uint64 {
-	if m != nil && m.MaxFileKey != nil {
-		return *m.MaxFileKey
-	}
-	return 0
-}
-
-func (m *JoinMessage) GetDataCenter() string {
-	if m != nil && m.DataCenter != nil {
-		return *m.DataCenter
-	}
-	return ""
-}
-
-func (m *JoinMessage) GetRack() string {
-	if m != nil && m.Rack != nil {
-		return *m.Rack
-	}
-	return ""
-}
-
-func (m *JoinMessage) GetVolumes() []*VolumeInformationMessage {
-	if m != nil {
-		return m.Volumes
-	}
-	return nil
-}
-
-func (m *JoinMessage) GetAdminPort() uint32 {
-	if m != nil && m.AdminPort != nil {
-		return *m.AdminPort
-	}
-	return 0
-}
-
-type CollectionSetting struct {
-	Collection             *string  `protobuf:"bytes,1,opt,name=collection" json:"collection,omitempty"`
-	ReplicaPlacement       *string  `protobuf:"bytes,2,opt,name=replica_placement" json:"replica_placement,omitempty"`
-	VacuumGarbageThreshold *float32 `protobuf:"fixed32,3,opt,name=vacuum_garbage_threshold" json:"vacuum_garbage_threshold,omitempty"`
-	XXX_unrecognized       []byte   `json:"-"`
-}
-
-func (m *CollectionSetting) Reset()         { *m = CollectionSetting{} }
-func (m *CollectionSetting) String() string { return proto.CompactTextString(m) }
-func (*CollectionSetting) ProtoMessage()    {}
-
-func (m *CollectionSetting) GetCollection() string {
-	if m != nil && m.Collection != nil {
-		return *m.Collection
-	}
-	return ""
-}
-
-func (m *CollectionSetting) GetReplicaPlacement() string {
-	if m != nil && m.ReplicaPlacement != nil {
-		return *m.ReplicaPlacement
-	}
-	return ""
-}
-
-func (m *CollectionSetting) GetVacuumGarbageThreshold() float32 {
-	if m != nil && m.VacuumGarbageThreshold != nil {
-		return *m.VacuumGarbageThreshold
-	}
-	return 0
-}
-
-type GlobalSetting struct {
-	Settings         []*CollectionSetting `protobuf:"bytes,1,rep,name=settings" json:"settings,omitempty"`
-	MasterPeers      []string             `protobuf:"bytes,2,rep,name=master_peers" json:"master_peers,omitempty"`
-	XXX_unrecognized []byte               `json:"-"`
-}
-
-func (m *GlobalSetting) Reset()         { *m = GlobalSetting{} }
-func (m *GlobalSetting) String() string { return proto.CompactTextString(m) }
-func (*GlobalSetting) ProtoMessage()    {}
-
-func (m *GlobalSetting) GetSettings() []*CollectionSetting {
-	if m != nil {
-		return m.Settings
-	}
-	return nil
-}
-
-func (m *GlobalSetting) GetMasterPeers() []string {
-	if m != nil {
-		return m.MasterPeers
-	}
-	return nil
-}
-
-type JoinResponse struct {
-	Settings         *GlobalSetting `protobuf:"bytes,1,opt,name=settings" json:"settings,omitempty"`
-	XXX_unrecognized []byte         `json:"-"`
-}
-
-func (m *JoinResponse) Reset()         { *m = JoinResponse{} }
-func (m *JoinResponse) String() string { return proto.CompactTextString(m) }
-func (*JoinResponse) ProtoMessage()    {}
-
-func (m *JoinResponse) GetSettings() *GlobalSetting {
-	if m != nil {
-		return m.Settings
-	}
-	return nil
-}
-
-func init() {
-}
diff --git a/go/proto/system_message.proto b/go/proto/system_message.proto
deleted file mode 100644
index 30dd2a22c..000000000
--- a/go/proto/system_message.proto
+++ /dev/null
@@ -1,45 +0,0 @@
-package operation;
-
-message VolumeInformationMessage {
-    required uint32 id = 1;
-    required uint64 size = 2;
-    optional string collection = 3;
-    required uint64 file_count = 4;
-    required uint64 delete_count = 5;
-    required uint64 deleted_byte_count = 6;
-    optional bool read_only = 7;
-    optional uint32 replica_placement = 8;
-    optional uint32 version = 9 [default=2];
-    optional uint32 ttl = 10;
-}
-
-message JoinMessage {
-    optional bool   is_init = 1;
-    required string ip = 2;
-    required uint32 port = 3;
-    optional string public_url = 4;
-    required uint32 max_volume_count = 5;
-    required uint64 max_file_key = 6;
-    optional string data_center = 7;
-    optional string rack = 8;
-    repeated VolumeInformationMessage volumes = 9;
-    optional uint32 admin_port = 10;
-}
-
-
-message CollectionSetting {
-    optional string collection = 1;
-    optional string replica_placement = 2;
-    optional float vacuum_garbage_threshold = 3;
-}
-
-message GlobalSetting {
-    repeated CollectionSetting settings = 1;
-    repeated string master_peers = 2;
-}
-
-message JoinResponse {
-    optional GlobalSetting settings = 1;
-}
-
-
diff --git a/go/storage/store.go b/go/storage/store.go
index b2fcdedc7..53f5edebf 100644
--- a/go/storage/store.go
+++ b/go/storage/store.go
@@ -1,7 +1,6 @@
 package storage
 
 import (
-	"encoding/json"
 	"errors"
 	"fmt"
 	"math/rand"
@@ -10,11 +9,12 @@ import (
 
 	"sync"
 
+	"encoding/json"
 	"github.com/chrislusf/seaweedfs/go/glog"
 	"github.com/chrislusf/seaweedfs/go/operation"
 	"github.com/chrislusf/seaweedfs/go/security"
 	"github.com/chrislusf/seaweedfs/go/util"
-	"github.com/golang/protobuf/proto"
+	"github.com/chrislusf/seaweedfs/go/weedpb"
 )
 
 const (
@@ -71,13 +71,13 @@ func (mn *MasterNodes) findMaster() (string, error) {
  * A VolumeServer contains one Store
  */
 type Store struct {
-	Ip              string
+	joinKey         string
+	ip              string
 	Port            int
 	PublicUrl       string
 	Locations       []*DiskLocation
 	dataCenter      string //optional informaton, overwriting master setting if exists
 	rack            string //optional information, overwriting master setting if exists
-	connected       bool
 	volumeSizeLimit uint64 //read from the master
 	masterNodes     *MasterNodes
 	needleMapKind   NeedleMapType
@@ -86,15 +86,15 @@ type Store struct {
 }
 
 func (s *Store) String() (str string) {
-	str = fmt.Sprintf("Ip:%s, Port:%d, PublicUrl:%s, dataCenter:%s, rack:%s, connected:%v, volumeSizeLimit:%d, masterNodes:%s",
-		s.Ip, s.Port, s.PublicUrl, s.dataCenter, s.rack, s.IsConnected(), s.GetVolumeSizeLimit(), s.masterNodes)
+	str = fmt.Sprintf("Ip:%s, Port:%d, PublicUrl:%s, dataCenter:%s, rack:%s, joinKey:%v, volumeSizeLimit:%d, masterNodes:%s",
+		s.GetIP(), s.Port, s.PublicUrl, s.dataCenter, s.rack, s.GetJoinKey(), s.GetVolumeSizeLimit(), s.masterNodes)
 	return
 }
 
 func NewStore(port int, ip, publicUrl string, dirnames []string, maxVolumeCounts []int, needleMapKind NeedleMapType) (s *Store) {
 	s = &Store{
 		Port:          port,
-		Ip:            ip,
+		ip:            ip,
 		PublicUrl:     publicUrl,
 		TaskManager:   NewTaskManager(),
 		needleMapKind: needleMapKind,
@@ -219,7 +219,7 @@ func (s *Store) SendHeartbeatToMaster() (masterNode string, secretKey security.S
 	if e != nil {
 		return
 	}
-	var volumeMessages []*operation.VolumeInformationMessage
+	var volumeMessages []*weedpb.VolumeInformationMessage
 	maxVolumeCount := 0
 	var maxFileKey uint64
 	for _, location := range s.Locations {
@@ -230,16 +230,16 @@ func (s *Store) SendHeartbeatToMaster() (masterNode string, secretKey security.S
 				maxFileKey = v.nm.MaxFileKey()
 			}
 			if !v.expired(s.GetVolumeSizeLimit()) {
-				volumeMessage := &operation.VolumeInformationMessage{
-					Id:               proto.Uint32(uint32(v.Id)),
-					Size:             proto.Uint64(uint64(v.Size())),
-					Collection:       proto.String(v.Collection),
-					FileCount:        proto.Uint64(uint64(v.nm.FileCount())),
-					DeleteCount:      proto.Uint64(uint64(v.nm.DeletedCount())),
-					DeletedByteCount: proto.Uint64(v.nm.DeletedSize()),
-					ReadOnly:         proto.Bool(v.IsReadOnly()),
-					Version:          proto.Uint32(uint32(v.Version())),
-					Ttl:              proto.Uint32(v.Ttl.ToUint32()),
+				volumeMessage := &weedpb.VolumeInformationMessage{
+					Id:               uint32(v.Id),
+					Size:             uint64(v.Size()),
+					Collection:       v.Collection,
+					FileCount:        uint64(v.nm.FileCount()),
+					DeleteCount:      uint64(v.nm.DeletedCount()),
+					DeletedByteCount: v.nm.DeletedSize(),
+					ReadOnly:         v.IsReadOnly(),
+					Version:          uint32(v.Version()),
+					Ttl:              v.Ttl.ToUint32(),
 				}
 				volumeMessages = append(volumeMessages, volumeMessage)
 			} else {
@@ -257,44 +257,44 @@ func (s *Store) SendHeartbeatToMaster() (masterNode string, secretKey security.S
 		}
 	}
 
-	joinMessage := &operation.JoinMessage{
-		IsInit:         proto.Bool(!s.IsConnected()),
-		Ip:             proto.String(s.Ip),
-		Port:           proto.Uint32(uint32(s.Port)),
-		PublicUrl:      proto.String(s.PublicUrl),
-		MaxVolumeCount: proto.Uint32(uint32(maxVolumeCount)),
-		MaxFileKey:     proto.Uint64(maxFileKey),
-		DataCenter:     proto.String(s.dataCenter),
-		Rack:           proto.String(s.rack),
+	joinMsgV2 := &weedpb.JoinMessageV2{
+		JoinKey:        s.GetJoinKey(),
+		Ip:             s.GetIP(),
+		Port:           uint32(s.Port),
+		PublicUrl:      s.PublicUrl,
+		MaxVolumeCount: uint32(maxVolumeCount),
+		MaxFileKey:     maxFileKey,
+		DataCenter:     s.dataCenter,
+		Rack:           s.rack,
 		Volumes:        volumeMessages,
 	}
-
-	data, err := proto.Marshal(joinMessage)
-	if err != nil {
-		return "", "", err
-	}
-
-	joinUrl := util.MkUrl(masterNode, "/dir/join", nil)
+	ret := &weedpb.JoinResponse{}
+	joinUrl := util.MkUrl(masterNode, "/dir/join2", nil)
 	glog.V(4).Infof("Connecting to %s ...", joinUrl)
-
-	jsonBlob, err := util.PostBytes(joinUrl, data)
-	if err != nil {
+	if err := util.PostPbMsg(joinUrl, joinMsgV2, ret); err != nil {
 		s.masterNodes.reset()
 		return "", "", err
 	}
-	var ret operation.JoinResult
-	if err := json.Unmarshal(jsonBlob, &ret); err != nil {
-		glog.V(0).Infof("Failed to join %s with response: %s", joinUrl, string(jsonBlob))
-		s.masterNodes.reset()
-		return masterNode, "", err
-	}
+
 	if ret.Error != "" {
 		s.masterNodes.reset()
 		return masterNode, "", errors.New(ret.Error)
 	}
-	s.SetVolumeSizeLimit(ret.VolumeSizeLimit)
+	if ret.JoinKey != s.GetJoinKey() {
+		if glog.V(4) {
+			jsonData, _ := json.Marshal(ret)
+			glog.V(4).Infof("dir join sync settings: %v", string(jsonData))
+		}
+		s.SetJoinKey(ret.JoinKey)
+		if ret.JoinIp != "" {
+			s.SetIP(ret.JoinIp)
+		}
+		if ret.VolumeSizeLimit != 0 {
+			s.SetVolumeSizeLimit(ret.VolumeSizeLimit)
+		}
+	}
+	//todo
 	secretKey = security.Secret(ret.SecretKey)
-	s.SetConnected(true)
 	return
 }
 func (s *Store) Close() {
@@ -367,14 +367,26 @@ func (s *Store) SetVolumeSizeLimit(sz uint64) {
 	s.volumeSizeLimit = sz
 }
 
-func (s *Store) IsConnected() bool {
+func (s *Store) GetIP() string {
+	s.mutex.RLock()
+	defer s.mutex.RUnlock()
+	return s.ip
+}
+
+func (s *Store) SetIP(ip string) {
+	s.mutex.Lock()
+	defer s.mutex.Unlock()
+	s.ip = ip
+}
+
+func (s *Store) GetJoinKey() string {
 	s.mutex.RLock()
 	defer s.mutex.RUnlock()
-	return s.connected
+	return s.joinKey
 }
 
-func (s *Store) SetConnected(b bool) {
+func (s *Store) SetJoinKey(k string) {
 	s.mutex.Lock()
 	defer s.mutex.Unlock()
-	s.connected = b
+	s.joinKey = k
 }
diff --git a/go/storage/volume_info.go b/go/storage/volume_info.go
index 1dab44cb2..f2973cb8f 100644
--- a/go/storage/volume_info.go
+++ b/go/storage/volume_info.go
@@ -4,7 +4,7 @@ import (
 	"fmt"
 	"sort"
 
-	"github.com/chrislusf/seaweedfs/go/operation"
+	"github.com/chrislusf/seaweedfs/go/weedpb"
 )
 
 type VolumeInfo struct {
@@ -19,18 +19,18 @@ type VolumeInfo struct {
 	ReadOnly         bool
 }
 
-func NewVolumeInfo(m *operation.VolumeInformationMessage) (vi *VolumeInfo, err error) {
+func NewVolumeInfo(m *weedpb.VolumeInformationMessage) (vi *VolumeInfo, err error) {
 	vi = &VolumeInfo{
-		Id:               VolumeId(*m.Id),
-		Size:             *m.Size,
-		Collection:       *m.Collection,
-		FileCount:        int(*m.FileCount),
-		DeleteCount:      int(*m.DeleteCount),
-		DeletedByteCount: *m.DeletedByteCount,
-		ReadOnly:         *m.ReadOnly,
-		Version:          Version(*m.Version),
+		Id:               VolumeId(m.Id),
+		Size:             m.Size,
+		Collection:       m.Collection,
+		FileCount:        int(m.FileCount),
+		DeleteCount:      int(m.DeleteCount),
+		DeletedByteCount: m.DeletedByteCount,
+		ReadOnly:         m.ReadOnly,
+		Version:          Version(m.Version),
 	}
-	vi.Ttl = LoadTTLFromUint32(*m.Ttl)
+	vi.Ttl = LoadTTLFromUint32(m.Ttl)
 	return vi, nil
 }
 
diff --git a/go/topology/store_replicate.go b/go/topology/store_replicate.go
index 01d9b88ea..b030cd8ca 100644
--- a/go/topology/store_replicate.go
+++ b/go/topology/store_replicate.go
@@ -41,6 +41,7 @@ func ReplicatedWrite(masterNode string, s *storage.Store,
 			}
 
 			u := util.MkUrl(location.Url, r.URL.Path, args)
+			glog.V(4).Infoln("write replication to", u)
 			_, err := operation.Upload(u,
 				string(needle.Name), bytes.NewReader(needle.Data), needle.IsGzipped(), string(needle.Mime),
 				jwt)
@@ -85,7 +86,7 @@ func distributedOperation(masterNode string, store *storage.Store, volumeId stor
 	}
 	if lookupResult, lookupErr := operation.LookupNoCache(masterNode, volumeId.String(), collection); lookupErr == nil {
 		length := 0
-		selfUrl := net.JoinHostPort(store.Ip, strconv.Itoa(store.Port))
+		selfUrl := net.JoinHostPort(store.GetIP(), strconv.Itoa(store.Port))
 		results := make(chan bool)
 		for _, location := range lookupResult.Locations {
 			if location.Url != selfUrl {
diff --git a/go/topology/topology.go b/go/topology/topology.go
index b8a22e94f..f6d015f88 100644
--- a/go/topology/topology.go
+++ b/go/topology/topology.go
@@ -5,12 +5,15 @@ import (
 	"io/ioutil"
 	"math/rand"
 
+	"strconv"
+	"time"
+
 	"github.com/chrislusf/raft"
 	"github.com/chrislusf/seaweedfs/go/glog"
-	"github.com/chrislusf/seaweedfs/go/operation"
 	"github.com/chrislusf/seaweedfs/go/sequence"
 	"github.com/chrislusf/seaweedfs/go/storage"
 	"github.com/chrislusf/seaweedfs/go/util"
+	"github.com/chrislusf/seaweedfs/go/weedpb"
 )
 
 type Topology struct {
@@ -19,6 +22,7 @@ type Topology struct {
 	collectionMap      *util.ConcurrentMap
 	pulse              int64
 	volumeSizeLimit    uint64
+	joinKey            string
 	Sequence           sequence.Sequencer
 	CollectionSettings *storage.CollectionSettings
 	configuration      *Configuration
@@ -39,6 +43,7 @@ func NewTopology(id string, confFile string, cs *storage.CollectionSettings, seq
 	t.pulse = int64(pulse)
 	t.volumeSizeLimit = volumeSizeLimit
 	t.CollectionSettings = cs
+	t.ReGenJoinKey()
 
 	t.Sequence = seq
 
@@ -86,6 +91,25 @@ func (t *Topology) Leader() (string, error) {
 	return l, nil
 }
 
+func (t *Topology) GetJoinKey() string {
+	t.mutex.RLock()
+	defer t.mutex.RUnlock()
+	return t.joinKey
+}
+
+func (t *Topology) ReGenJoinKey() {
+	t.mutex.Lock()
+	defer t.mutex.Unlock()
+	t.joinKey = strconv.FormatInt(time.Now().UnixNano(), 16)
+}
+
+func (t *Topology) GetVolumeSizeLimit() uint64 {
+	// volumeSizeLimit is only for read
+	//t.mutex.RLock()
+	//defer t.mutex.RUnlock()
+	return t.volumeSizeLimit
+}
+
 func (t *Topology) loadConfiguration(configurationFile string) error {
 	b, e := ioutil.ReadFile(configurationFile)
 	if e == nil {
@@ -159,18 +183,18 @@ func (t *Topology) UnRegisterVolumeLayout(v *storage.VolumeInfo, dn *DataNode) {
 	t.GetVolumeLayout(v.Collection, v.Ttl).UnRegisterVolume(v, dn)
 }
 
-func (t *Topology) ProcessJoinMessage(joinMessage *operation.JoinMessage) {
-	t.Sequence.SetMax(*joinMessage.MaxFileKey)
-	dcName, rackName := t.configuration.Locate(*joinMessage.Ip, *joinMessage.DataCenter, *joinMessage.Rack)
+func (t *Topology) ProcessJoinMessage(joinMessage *weedpb.JoinMessage) {
+	t.Sequence.SetMax(joinMessage.MaxFileKey)
+	dcName, rackName := t.configuration.Locate(joinMessage.Ip, joinMessage.DataCenter, joinMessage.Rack)
 	dc := t.GetOrCreateDataCenter(dcName)
 	rack := dc.GetOrCreateRack(rackName)
-	dn := rack.FindDataNode(*joinMessage.Ip, int(*joinMessage.Port))
-	if *joinMessage.IsInit && dn != nil {
+	dn := rack.FindDataNode(joinMessage.Ip, int(joinMessage.Port))
+	if joinMessage.IsInit && dn != nil {
 		t.UnRegisterDataNode(dn)
 	}
-	dn = rack.GetOrCreateDataNode(*joinMessage.Ip,
-		int(*joinMessage.Port), *joinMessage.PublicUrl,
-		int(*joinMessage.MaxVolumeCount))
+	dn = rack.GetOrCreateDataNode(joinMessage.Ip,
+		int(joinMessage.Port), joinMessage.PublicUrl,
+		int(joinMessage.MaxVolumeCount))
 	var volumeInfos []*storage.VolumeInfo
 	for _, v := range joinMessage.Volumes {
 		if vi, err := storage.NewVolumeInfo(v); err == nil {
@@ -190,6 +214,37 @@ func (t *Topology) ProcessJoinMessage(joinMessage *operation.JoinMessage) {
 
 }
 
+func (t *Topology) ProcessJoinMessageV2(joinMsgV2 *weedpb.JoinMessageV2) {
+	t.Sequence.SetMax(joinMsgV2.MaxFileKey)
+	dcName, rackName := t.configuration.Locate(joinMsgV2.Ip, joinMsgV2.DataCenter, joinMsgV2.Rack)
+	dc := t.GetOrCreateDataCenter(dcName)
+	rack := dc.GetOrCreateRack(rackName)
+	dn := rack.FindDataNode(joinMsgV2.Ip, int(joinMsgV2.Port))
+	if joinMsgV2.JoinKey == "" && dn != nil {
+		t.UnRegisterDataNode(dn)
+	}
+	dn = rack.GetOrCreateDataNode(joinMsgV2.Ip,
+		int(joinMsgV2.Port), joinMsgV2.PublicUrl,
+		int(joinMsgV2.MaxVolumeCount))
+	var volumeInfos []*storage.VolumeInfo
+	for _, v := range joinMsgV2.Volumes {
+		if vi, err := storage.NewVolumeInfo(v); err == nil {
+			volumeInfos = append(volumeInfos, vi)
+		} else {
+			glog.V(0).Infoln("Fail to convert joined volume information:", err.Error())
+		}
+	}
+
+	deletedVolumes := dn.UpdateVolumes(volumeInfos)
+	for _, v := range volumeInfos {
+		t.RegisterVolumeLayout(v, dn)
+	}
+	for _, v := range deletedVolumes {
+		t.UnRegisterVolumeLayout(v, dn)
+	}
+
+}
+
 func (t *Topology) GetOrCreateDataCenter(dcName string) *DataCenter {
 	n := t.GetChildren(NodeId(dcName))
 	if n != nil {
diff --git a/go/util/http_util.go b/go/util/http_util.go
index 722c63276..13cc1d8ed 100644
--- a/go/util/http_util.go
+++ b/go/util/http_util.go
@@ -15,6 +15,7 @@ import (
 
 	"github.com/chrislusf/seaweedfs/go/glog"
 	"github.com/chrislusf/seaweedfs/go/security"
+	"github.com/golang/protobuf/proto"
 	"github.com/pierrec/lz4"
 	"strconv"
 )
@@ -56,6 +57,34 @@ func PostBytes(url string, body []byte) ([]byte, error) {
 	return b, nil
 }
 
+func PostPbMsg(url string, msg proto.Message, ret proto.Message) error {
+	data, err := proto.Marshal(msg)
+	if err != nil {
+		return err
+	}
+	req, err := http.NewRequest("POST", url, bytes.NewReader(data))
+	if err != nil {
+		return err
+	}
+	req.Header.Set("Content-Type", "application/protobuf")
+	req.Header.Set("Accept", "application/protobuf")
+	resp, err := client.Do(req)
+	if err != nil {
+		return fmt.Errorf("Post to %s: %v", url, err)
+	}
+	defer resp.Body.Close()
+	retBlob, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return fmt.Errorf("Read response body: %v", err)
+	}
+
+	if err := proto.Unmarshal(retBlob, ret); err != nil {
+		glog.V(0).Infof("Failed to umarshal pb %s with response: %s", url, string(retBlob))
+		return err
+	}
+	return nil
+}
+
 func PostEx(host, path string, values url.Values) (content []byte, statusCode int, e error) {
 	url := MkUrl(host, path, nil)
 	glog.V(4).Infoln("Post", url+"?"+values.Encode())
diff --git a/go/weed/weed_server/common.go b/go/weed/weed_server/common.go
index 582e3e4ef..ada571f49 100644
--- a/go/weed/weed_server/common.go
+++ b/go/weed/weed_server/common.go
@@ -4,19 +4,21 @@ import (
 	"bytes"
 	"encoding/json"
 	"errors"
-	"fmt"
 	"net/http"
 	"path/filepath"
 	"strconv"
 	"strings"
 	"time"
 
+	"io/ioutil"
+
 	"github.com/chrislusf/seaweedfs/go/glog"
 	"github.com/chrislusf/seaweedfs/go/operation"
 	"github.com/chrislusf/seaweedfs/go/security"
 	"github.com/chrislusf/seaweedfs/go/stats"
 	"github.com/chrislusf/seaweedfs/go/storage"
 	"github.com/chrislusf/seaweedfs/go/util"
+	"github.com/golang/protobuf/proto"
 )
 
 var serverStats *stats.ServerStats
@@ -28,42 +30,57 @@ func init() {
 
 }
 
-func writeJson(w http.ResponseWriter, r *http.Request, httpStatus int, obj interface{}) (err error) {
-	var bytes []byte
-	if r.FormValue("pretty") != "" {
-		bytes, err = json.MarshalIndent(obj, "", "  ")
-	} else {
-		bytes, err = json.Marshal(obj)
-	}
+func readObjRequest(r *http.Request, obj interface{}) error {
+	body, err := ioutil.ReadAll(r.Body)
 	if err != nil {
-		return
+		return err
 	}
-	callback := r.FormValue("callback")
-	if callback == "" {
-		w.Header().Set("Content-Type", "application/json")
-		w.WriteHeader(httpStatus)
-		_, err = w.Write(bytes)
+	if pbMsg, ok := obj.(proto.Message); ok && strings.Contains(r.Header.Get("Content-Type"), "protobuf") {
+		if err := proto.Unmarshal(body, pbMsg); err != nil {
+			return err
+		}
 	} else {
-		w.Header().Set("Content-Type", "application/javascript")
-		w.WriteHeader(httpStatus)
-		if _, err = w.Write([]uint8(callback)); err != nil {
-			return
+		if err := json.Unmarshal(body, obj); err != nil {
+			return err
 		}
-		if _, err = w.Write([]uint8("(")); err != nil {
-			return
+	}
+	return nil
+}
+
+func writeObjResponse(w http.ResponseWriter, r *http.Request, httpStatus int, obj interface{}) (err error) {
+	var (
+		bytes       []byte
+		contentType string
+	)
+	if pbMsg, ok := obj.(proto.Message); ok && strings.Contains(r.Header.Get("Accept"), "protobuf") {
+		bytes, err = proto.Marshal(pbMsg)
+		contentType = "application/protobuf"
+	} else {
+		if r.FormValue("pretty") != "" {
+			bytes, err = json.MarshalIndent(obj, "", "  ")
+		} else {
+			bytes, err = json.Marshal(obj)
 		}
-		fmt.Fprint(w, string(bytes))
-		if _, err = w.Write([]uint8(")")); err != nil {
-			return
+		if callback := r.FormValue("callback"); callback != "" {
+			contentType = "application/javascript"
+			bytes = []byte(callback + "(" + string(bytes) + ")")
+		} else {
+			contentType = "application/json"
 		}
 	}
 
+	if err != nil {
+		return
+	}
+	w.Header().Set("Content-Type", contentType)
+	w.WriteHeader(httpStatus)
+	_, err = w.Write(bytes)
 	return
 }
 
 // wrapper for writeJson - just logs errors
 func writeJsonQuiet(w http.ResponseWriter, r *http.Request, httpStatus int, obj interface{}) {
-	if err := writeJson(w, r, httpStatus, obj); err != nil {
+	if err := writeObjResponse(w, r, httpStatus, obj); err != nil {
 		glog.V(0).Infof("error writing JSON %s: %v", obj, err)
 	}
 }
diff --git a/go/weed/weed_server/master_server.go b/go/weed/weed_server/master_server.go
index 07d9a4722..301ff2160 100644
--- a/go/weed/weed_server/master_server.go
+++ b/go/weed/weed_server/master_server.go
@@ -67,6 +67,7 @@ func NewMasterServer(r *mux.Router, port int, metaFolder string,
 	r.HandleFunc("/dir/assign", ms.proxyToLeader(ms.guard.WhiteList(ms.dirAssignHandler)))
 	r.HandleFunc("/dir/lookup", ms.proxyToLeader(ms.guard.WhiteList(ms.dirLookupHandler)))
 	r.HandleFunc("/dir/join", ms.proxyToLeader(ms.guard.WhiteList(ms.dirJoinHandler)))
+	r.HandleFunc("/dir/join2", ms.proxyToLeader(ms.guard.WhiteList(ms.dirJoin2Handler)))
 	r.HandleFunc("/dir/status", ms.proxyToLeader(ms.guard.WhiteList(ms.dirStatusHandler)))
 	r.HandleFunc("/col/delete", ms.proxyToLeader(ms.guard.WhiteList(ms.collectionDeleteHandler)))
 	r.HandleFunc("/vol/lookup", ms.proxyToLeader(ms.guard.WhiteList(ms.volumeLookupHandler)))
diff --git a/go/weed/weed_server/master_server_handlers_admin.go b/go/weed/weed_server/master_server_handlers_admin.go
index b06440d85..767ecb85d 100644
--- a/go/weed/weed_server/master_server_handlers_admin.go
+++ b/go/weed/weed_server/master_server_handlers_admin.go
@@ -14,10 +14,10 @@ import (
 	"net"
 
 	"github.com/chrislusf/seaweedfs/go/glog"
-	"github.com/chrislusf/seaweedfs/go/operation"
 	"github.com/chrislusf/seaweedfs/go/storage"
 	"github.com/chrislusf/seaweedfs/go/topology"
 	"github.com/chrislusf/seaweedfs/go/util"
+	"github.com/chrislusf/seaweedfs/go/weedpb"
 	"github.com/golang/protobuf/proto"
 )
 
@@ -37,23 +37,24 @@ func (ms *MasterServer) collectionDeleteHandler(w http.ResponseWriter, r *http.R
 	ms.Topo.DeleteCollection(r.FormValue("collection"))
 }
 
+// deprecated
 func (ms *MasterServer) dirJoinHandler(w http.ResponseWriter, r *http.Request) {
 	body, err := ioutil.ReadAll(r.Body)
 	if err != nil {
 		writeJsonError(w, r, http.StatusBadRequest, err)
 		return
 	}
-	joinMessage := &operation.JoinMessage{}
+	joinMessage := &weedpb.JoinMessage{}
 	if err = proto.Unmarshal(body, joinMessage); err != nil {
 		writeJsonError(w, r, http.StatusBadRequest, err)
 		return
 	}
-	if *joinMessage.Ip == "" {
+	if joinMessage.Ip == "" {
 		if ip, _, e := net.SplitHostPort(r.RemoteAddr); e == nil {
-			*joinMessage.Ip = ip
+			joinMessage.Ip = ip
 		} else {
 			glog.V(2).Infof("SplitHostPort (%s) error, %v", r.RemoteAddr, e)
-			*joinMessage.Ip = r.RemoteAddr
+			joinMessage.Ip = r.RemoteAddr
 		}
 	}
 	if glog.V(4) {
@@ -65,14 +66,51 @@ func (ms *MasterServer) dirJoinHandler(w http.ResponseWriter, r *http.Request) {
 			glog.V(4).Infoln("Proto size", len(body), "json size", len(jsonData), string(jsonData))
 		}
 	}
-
 	ms.Topo.ProcessJoinMessage(joinMessage)
-	writeJsonQuiet(w, r, http.StatusOK, operation.JoinResult{
+	type JoinResult struct {
+		VolumeSizeLimit uint64 `json:"VolumeSizeLimit,omitempty"`
+		SecretKey       string `json:"secretKey,omitempty"`
+		Error           string `json:"error,omitempty"`
+	}
+	writeJsonQuiet(w, r, http.StatusOK, JoinResult{
 		VolumeSizeLimit: uint64(ms.volumeSizeLimitMB) * 1024 * 1024,
 		SecretKey:       string(ms.guard.SecretKey),
 	})
 }
 
+func (ms *MasterServer) dirJoin2Handler(w http.ResponseWriter, r *http.Request) {
+	joinResp := &weedpb.JoinResponse{}
+	joinMsgV2 := &weedpb.JoinMessageV2{}
+
+	if err := readObjRequest(r, joinMsgV2); err != nil {
+		joinResp.Error = err.Error()
+		writeObjResponse(w, r, http.StatusBadRequest, joinResp)
+		return
+	}
+	if joinMsgV2.Ip == "" {
+		if ip, _, e := net.SplitHostPort(r.RemoteAddr); e == nil {
+			joinMsgV2.Ip = ip
+		} else {
+			glog.V(2).Infof("SplitHostPort (%s) error, %v", r.RemoteAddr, e)
+			joinMsgV2.Ip = r.RemoteAddr
+		}
+	}
+	if glog.V(4) {
+		jsonData, _ := json.Marshal(joinMsgV2)
+		glog.V(4).Infoln("join proto:", string(jsonData))
+	}
+
+	ms.Topo.ProcessJoinMessageV2(joinMsgV2)
+
+	joinResp.JoinKey = ms.Topo.GetJoinKey()
+	if joinMsgV2.JoinKey != joinResp.JoinKey {
+		joinResp.JoinIp = joinMsgV2.Ip
+		joinResp.VolumeSizeLimit = ms.Topo.GetVolumeSizeLimit()
+		joinResp.SecretKey = string(ms.guard.SecretKey)
+	}
+	writeObjResponse(w, r, http.StatusOK, joinResp)
+}
+
 func (ms *MasterServer) dirStatusHandler(w http.ResponseWriter, r *http.Request) {
 	m := make(map[string]interface{})
 	m["Version"] = util.VERSION
diff --git a/go/weed/weed_server/volume_server_handlers_admin.go b/go/weed/weed_server/volume_server_handlers_admin.go
index 779d6f99d..40a4642e5 100644
--- a/go/weed/weed_server/volume_server_handlers_admin.go
+++ b/go/weed/weed_server/volume_server_handlers_admin.go
@@ -117,5 +117,5 @@ func (vs *VolumeServer) setVolumeOptionHandler(w http.ResponseWriter, r *http.Re
 		result["errors"] = errs
 	}
 
-	writeJson(w, r, http.StatusAccepted, result)
+	writeObjResponse(w, r, http.StatusAccepted, result)
 }
diff --git a/go/proto/Makefile b/go/weedpb/Makefile
similarity index 74%
rename from go/proto/Makefile
rename to go/weedpb/Makefile
index 73af851dd..3f6ec2cc6 100644
--- a/go/proto/Makefile
+++ b/go/weedpb/Makefile
@@ -1,4 +1,4 @@
-TARG=../operation
+TARG=./
 
 all:
 	protoc --go_out=$(TARG) system_message.proto
diff --git a/go/weedpb/system_message.pb.go b/go/weedpb/system_message.pb.go
new file mode 100644
index 000000000..fa17b7bf0
--- /dev/null
+++ b/go/weedpb/system_message.pb.go
@@ -0,0 +1,180 @@
+// Code generated by protoc-gen-go.
+// source: system_message.proto
+// DO NOT EDIT!
+
+/*
+Package weedpb is a generated protocol buffer package.
+
+It is generated from these files:
+	system_message.proto
+
+It has these top-level messages:
+	VolumeInformationMessage
+	JoinMessage
+	JoinMessageV2
+	CollectionSetting
+	JoinResponse
+*/
+package weedpb
+
+import proto "github.com/golang/protobuf/proto"
+import fmt "fmt"
+import math "math"
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+const _ = proto.ProtoPackageIsVersion1
+
+type VolumeInformationMessage struct {
+	Id               uint32 `protobuf:"varint,1,opt,name=id" json:"id,omitempty"`
+	Size             uint64 `protobuf:"varint,2,opt,name=size" json:"size,omitempty"`
+	Collection       string `protobuf:"bytes,3,opt,name=collection" json:"collection,omitempty"`
+	FileCount        uint64 `protobuf:"varint,4,opt,name=file_count,json=fileCount" json:"file_count,omitempty"`
+	DeleteCount      uint64 `protobuf:"varint,5,opt,name=delete_count,json=deleteCount" json:"delete_count,omitempty"`
+	DeletedByteCount uint64 `protobuf:"varint,6,opt,name=deleted_byte_count,json=deletedByteCount" json:"deleted_byte_count,omitempty"`
+	ReadOnly         bool   `protobuf:"varint,7,opt,name=read_only,json=readOnly" json:"read_only,omitempty"`
+	ReplicaPlacement uint32 `protobuf:"varint,8,opt,name=replica_placement,json=replicaPlacement" json:"replica_placement,omitempty"`
+	Version          uint32 `protobuf:"varint,9,opt,name=version" json:"version,omitempty"`
+	Ttl              uint32 `protobuf:"varint,10,opt,name=ttl" json:"ttl,omitempty"`
+}
+
+func (m *VolumeInformationMessage) Reset()                    { *m = VolumeInformationMessage{} }
+func (m *VolumeInformationMessage) String() string            { return proto.CompactTextString(m) }
+func (*VolumeInformationMessage) ProtoMessage()               {}
+func (*VolumeInformationMessage) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{0} }
+
+// deprecated
+type JoinMessage struct {
+	IsInit         bool                        `protobuf:"varint,1,opt,name=is_init,json=isInit" json:"is_init,omitempty"`
+	Ip             string                      `protobuf:"bytes,2,opt,name=ip" json:"ip,omitempty"`
+	Port           uint32                      `protobuf:"varint,3,opt,name=port" json:"port,omitempty"`
+	PublicUrl      string                      `protobuf:"bytes,4,opt,name=public_url,json=publicUrl" json:"public_url,omitempty"`
+	MaxVolumeCount uint32                      `protobuf:"varint,5,opt,name=max_volume_count,json=maxVolumeCount" json:"max_volume_count,omitempty"`
+	MaxFileKey     uint64                      `protobuf:"varint,6,opt,name=max_file_key,json=maxFileKey" json:"max_file_key,omitempty"`
+	DataCenter     string                      `protobuf:"bytes,7,opt,name=data_center,json=dataCenter" json:"data_center,omitempty"`
+	Rack           string                      `protobuf:"bytes,8,opt,name=rack" json:"rack,omitempty"`
+	Volumes        []*VolumeInformationMessage `protobuf:"bytes,9,rep,name=volumes" json:"volumes,omitempty"`
+	AdminPort      uint32                      `protobuf:"varint,10,opt,name=admin_port,json=adminPort" json:"admin_port,omitempty"`
+}
+
+func (m *JoinMessage) Reset()                    { *m = JoinMessage{} }
+func (m *JoinMessage) String() string            { return proto.CompactTextString(m) }
+func (*JoinMessage) ProtoMessage()               {}
+func (*JoinMessage) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{1} }
+
+func (m *JoinMessage) GetVolumes() []*VolumeInformationMessage {
+	if m != nil {
+		return m.Volumes
+	}
+	return nil
+}
+
+type JoinMessageV2 struct {
+	JoinKey        string                      `protobuf:"bytes,1,opt,name=join_key,json=joinKey" json:"join_key,omitempty"`
+	Ip             string                      `protobuf:"bytes,2,opt,name=ip" json:"ip,omitempty"`
+	Port           uint32                      `protobuf:"varint,3,opt,name=port" json:"port,omitempty"`
+	PublicUrl      string                      `protobuf:"bytes,4,opt,name=public_url,json=publicUrl" json:"public_url,omitempty"`
+	MaxVolumeCount uint32                      `protobuf:"varint,5,opt,name=max_volume_count,json=maxVolumeCount" json:"max_volume_count,omitempty"`
+	MaxFileKey     uint64                      `protobuf:"varint,6,opt,name=max_file_key,json=maxFileKey" json:"max_file_key,omitempty"`
+	DataCenter     string                      `protobuf:"bytes,7,opt,name=data_center,json=dataCenter" json:"data_center,omitempty"`
+	Rack           string                      `protobuf:"bytes,8,opt,name=rack" json:"rack,omitempty"`
+	Volumes        []*VolumeInformationMessage `protobuf:"bytes,9,rep,name=volumes" json:"volumes,omitempty"`
+}
+
+func (m *JoinMessageV2) Reset()                    { *m = JoinMessageV2{} }
+func (m *JoinMessageV2) String() string            { return proto.CompactTextString(m) }
+func (*JoinMessageV2) ProtoMessage()               {}
+func (*JoinMessageV2) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{2} }
+
+func (m *JoinMessageV2) GetVolumes() []*VolumeInformationMessage {
+	if m != nil {
+		return m.Volumes
+	}
+	return nil
+}
+
+type CollectionSetting struct {
+	Collection       string `protobuf:"bytes,1,opt,name=collection" json:"collection,omitempty"`
+	ReplicaPlacement string `protobuf:"bytes,2,opt,name=replica_placement,json=replicaPlacement" json:"replica_placement,omitempty"`
+}
+
+func (m *CollectionSetting) Reset()                    { *m = CollectionSetting{} }
+func (m *CollectionSetting) String() string            { return proto.CompactTextString(m) }
+func (*CollectionSetting) ProtoMessage()               {}
+func (*CollectionSetting) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{3} }
+
+type JoinResponse struct {
+	Error              string               `protobuf:"bytes,1,opt,name=error" json:"error,omitempty"`
+	JoinKey            string               `protobuf:"bytes,2,opt,name=join_key,json=joinKey" json:"join_key,omitempty"`
+	JoinIp             string               `protobuf:"bytes,3,opt,name=join_ip,json=joinIp" json:"join_ip,omitempty"`
+	VolumeSizeLimit    uint64               `protobuf:"varint,4,opt,name=volume_size_limit,json=volumeSizeLimit" json:"volume_size_limit,omitempty"`
+	CollectionSettings []*CollectionSetting `protobuf:"bytes,5,rep,name=collection_settings,json=collectionSettings" json:"collection_settings,omitempty"`
+	SecretKey          string               `protobuf:"bytes,6,opt,name=secret_key,json=secretKey" json:"secret_key,omitempty"`
+}
+
+func (m *JoinResponse) Reset()                    { *m = JoinResponse{} }
+func (m *JoinResponse) String() string            { return proto.CompactTextString(m) }
+func (*JoinResponse) ProtoMessage()               {}
+func (*JoinResponse) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{4} }
+
+func (m *JoinResponse) GetCollectionSettings() []*CollectionSetting {
+	if m != nil {
+		return m.CollectionSettings
+	}
+	return nil
+}
+
+func init() {
+	proto.RegisterType((*VolumeInformationMessage)(nil), "weedpb.VolumeInformationMessage")
+	proto.RegisterType((*JoinMessage)(nil), "weedpb.JoinMessage")
+	proto.RegisterType((*JoinMessageV2)(nil), "weedpb.JoinMessageV2")
+	proto.RegisterType((*CollectionSetting)(nil), "weedpb.CollectionSetting")
+	proto.RegisterType((*JoinResponse)(nil), "weedpb.JoinResponse")
+}
+
+var fileDescriptor0 = []byte{
+	// 593 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x09, 0x6e, 0x88, 0x02, 0xff, 0xe4, 0x94, 0x5d, 0x6e, 0xd3, 0x40,
+	0x10, 0xc7, 0x15, 0xb7, 0x4d, 0xe2, 0x49, 0x53, 0xd2, 0xa5, 0x12, 0xae, 0x10, 0x50, 0xf2, 0x54,
+	0x01, 0x2a, 0x52, 0x79, 0xe3, 0xb1, 0x95, 0x90, 0x5a, 0x40, 0x54, 0x5b, 0xd1, 0x57, 0xe3, 0xd8,
+	0xd3, 0x6a, 0xa9, 0xed, 0xb5, 0x76, 0x37, 0x05, 0x73, 0x24, 0xee, 0x81, 0xc4, 0x6d, 0xb8, 0x02,
+	0xb3, 0xb3, 0x71, 0xe8, 0x07, 0x9c, 0x80, 0xb7, 0x99, 0xff, 0xcc, 0xda, 0x33, 0xbf, 0xd9, 0x59,
+	0xd8, 0xb2, 0xad, 0x75, 0x58, 0xa5, 0x15, 0x5a, 0x9b, 0x5d, 0xe0, 0x5e, 0x63, 0xb4, 0xd3, 0xa2,
+	0xff, 0x05, 0xb1, 0x68, 0x66, 0xd3, 0x9f, 0x11, 0x24, 0x67, 0xba, 0x9c, 0x57, 0x78, 0x54, 0x9f,
+	0x6b, 0x53, 0x65, 0x4e, 0xe9, 0xfa, 0x7d, 0x48, 0x15, 0x1b, 0x10, 0xa9, 0x22, 0xe9, 0xed, 0xf4,
+	0x76, 0xc7, 0x92, 0x2c, 0x21, 0x60, 0xd5, 0xaa, 0x6f, 0x98, 0x44, 0xa4, 0xac, 0x4a, 0xb6, 0xc5,
+	0x63, 0x80, 0x5c, 0x97, 0x25, 0xe6, 0xfe, 0x60, 0xb2, 0x42, 0x91, 0x58, 0x5e, 0x53, 0xc4, 0x23,
+	0x80, 0x73, 0x55, 0x62, 0x9a, 0xeb, 0x79, 0xed, 0x92, 0x55, 0x3e, 0x19, 0x7b, 0xe5, 0xd0, 0x0b,
+	0xe2, 0x29, 0xac, 0x17, 0x58, 0xa2, 0xeb, 0x12, 0xd6, 0x38, 0x61, 0x14, 0xb4, 0x90, 0xf2, 0x02,
+	0x44, 0x70, 0x8b, 0x74, 0xd6, 0x2e, 0x13, 0xfb, 0x9c, 0x38, 0x59, 0x44, 0x0e, 0xda, 0x2e, 0xfb,
+	0x21, 0xc4, 0x06, 0xb3, 0x22, 0xd5, 0x75, 0xd9, 0x26, 0x03, 0x4a, 0x1a, 0xca, 0xa1, 0x17, 0x3e,
+	0x90, 0x2f, 0x5e, 0xc2, 0xa6, 0xc1, 0xa6, 0x54, 0x79, 0x96, 0x36, 0x65, 0x96, 0x63, 0x85, 0xf4,
+	0xa5, 0xa1, 0xef, 0xef, 0x20, 0x4a, 0x7a, 0x72, 0xb2, 0x08, 0x9e, 0x74, 0x31, 0x91, 0xc0, 0xe0,
+	0x0a, 0x8d, 0xf5, 0xad, 0xc5, 0x8c, 0xa1, 0x73, 0xc5, 0x04, 0x56, 0x9c, 0x2b, 0x13, 0x60, 0xd5,
+	0x9b, 0xd3, 0x1f, 0x11, 0x8c, 0x8e, 0xb5, 0x5a, 0xd2, 0x7b, 0x00, 0x03, 0x65, 0x53, 0x55, 0x2b,
+	0xc7, 0x08, 0x87, 0xb2, 0xaf, 0xec, 0x11, 0x79, 0x8c, 0xb5, 0x61, 0x88, 0x31, 0x61, 0x6d, 0x3c,
+	0xd6, 0x46, 0x1b, 0xc7, 0xf0, 0xc6, 0x92, 0x6d, 0x8f, 0xad, 0x99, 0xcf, 0xa8, 0x98, 0x74, 0x6e,
+	0x4a, 0xc6, 0x16, 0xcb, 0x38, 0x28, 0x1f, 0x4d, 0x29, 0x76, 0x61, 0x52, 0x65, 0x5f, 0xd3, 0x2b,
+	0x9e, 0xdc, 0x35, 0x74, 0x63, 0xb9, 0x41, 0x7a, 0x18, 0x68, 0xe0, 0xb1, 0x03, 0xeb, 0x3e, 0x93,
+	0x67, 0x70, 0x89, 0xed, 0x82, 0x1b, 0x90, 0xf6, 0x86, 0xa4, 0xb7, 0xd8, 0x8a, 0x27, 0x30, 0x2a,
+	0x32, 0x97, 0xa5, 0x39, 0x35, 0x8c, 0x86, 0x99, 0xd1, 0x08, 0xbd, 0x74, 0xc8, 0x8a, 0xaf, 0xcf,
+	0x64, 0xf9, 0x25, 0x83, 0x8a, 0x25, 0xdb, 0xe2, 0x35, 0x81, 0xe1, 0xbf, 0x58, 0x02, 0xb3, 0xb2,
+	0x3b, 0xda, 0xdf, 0xd9, 0x0b, 0x37, 0x6a, 0xef, 0x5f, 0xb7, 0x49, 0x76, 0x07, 0x7c, 0x6f, 0x59,
+	0x51, 0xa9, 0x3a, 0xe5, 0xae, 0x03, 0xc1, 0x98, 0x95, 0x13, 0x12, 0xa6, 0xdf, 0x23, 0x18, 0x5f,
+	0xe3, 0x78, 0xb6, 0x2f, 0xb6, 0x61, 0xf8, 0x99, 0x04, 0xae, 0xbf, 0xc7, 0x45, 0x0c, 0xbc, 0xef,
+	0x8b, 0xff, 0xcf, 0x59, 0x4e, 0x3f, 0xc1, 0xe6, 0xe1, 0x72, 0xd9, 0x4e, 0xd1, 0x39, 0x55, 0x5f,
+	0xdc, 0xda, 0xc9, 0xde, 0x9d, 0x9d, 0x7c, 0xfe, 0xb7, 0x35, 0x08, 0x0c, 0xef, 0xac, 0xc0, 0xf4,
+	0x57, 0x0f, 0xd6, 0xfd, 0x38, 0x24, 0xda, 0x46, 0xd7, 0x16, 0xc5, 0x16, 0xac, 0xa1, 0x31, 0xda,
+	0x2c, 0x3e, 0x1c, 0x9c, 0x1b, 0x33, 0x8a, 0x6e, 0xce, 0x88, 0x16, 0x81, 0x43, 0x34, 0xa8, 0xf0,
+	0x3e, 0xf4, 0xbd, 0x7b, 0xd4, 0x88, 0x67, 0xb0, 0xb9, 0xa0, 0xee, 0x9f, 0x92, 0xb4, 0x54, 0x95,
+	0xea, 0x9e, 0x88, 0x7b, 0x21, 0x70, 0x4a, 0xfa, 0x3b, 0x2f, 0x8b, 0x63, 0xb8, 0xff, 0xa7, 0x83,
+	0xd4, 0x86, 0x4e, 0x2d, 0x0d, 0xca, 0x03, 0xdb, 0xee, 0x80, 0xdd, 0x61, 0x21, 0x45, 0x7e, 0x5b,
+	0xe2, 0x0b, 0x68, 0x31, 0x37, 0xe8, 0x96, 0x53, 0xa4, 0x0b, 0x11, 0x14, 0xaa, 0x77, 0xd6, 0xe7,
+	0x27, 0xf2, 0xd5, 0xef, 0x00, 0x00, 0x00, 0xff, 0xff, 0xdf, 0x7d, 0xe0, 0x05, 0x3a, 0x05, 0x00,
+	0x00,
+}
diff --git a/go/weedpb/system_message.proto b/go/weedpb/system_message.proto
new file mode 100644
index 000000000..b780bb929
--- /dev/null
+++ b/go/weedpb/system_message.proto
@@ -0,0 +1,61 @@
+syntax = "proto3";
+package weedpb;
+
+
+message VolumeInformationMessage {
+    uint32 id = 1;
+    uint64 size = 2;
+    string collection = 3;
+    uint64 file_count = 4;
+    uint64 delete_count = 5;
+    uint64 deleted_byte_count = 6;
+    bool read_only = 7;
+    uint32 replica_placement = 8 [deprecated=true];
+    uint32 version = 9;
+    uint32 ttl = 10;
+}
+
+// deprecated
+message JoinMessage {
+    bool   is_init = 1;
+    string ip = 2;
+    uint32 port = 3;
+    string public_url = 4;
+    uint32 max_volume_count = 5;
+    uint64 max_file_key = 6;
+    string data_center = 7;
+    string rack = 8;
+    repeated VolumeInformationMessage volumes = 9;
+    uint32 admin_port = 10;
+}
+
+message JoinMessageV2 {
+    string join_key = 1; //if data node is init, set join key  empty
+    string ip = 2;
+    uint32 port = 3;
+    string public_url = 4;
+    uint32 max_volume_count = 5;
+    uint64 max_file_key = 6;
+    string data_center = 7;
+    string rack = 8;
+    repeated VolumeInformationMessage volumes = 9;
+}
+
+message CollectionSetting {
+    string collection = 1;
+    string replica_placement = 2;
+//    float vacuum_garbage_threshold = 3;
+}
+
+message JoinResponse {
+    string error = 1;
+    string join_key = 2;
+    string join_ip = 3;
+    uint64 volume_size_limit = 4;
+    repeated CollectionSetting collection_settings = 5;
+    string secret_key = 6;
+//    repeated string master_peers = 7;
+
+}
+
+
diff --git a/go/operation/system_message_test.go b/go/weedpb/system_message_test.go
similarity index 50%
rename from go/operation/system_message_test.go
rename to go/weedpb/system_message_test.go
index d18ca49a4..21d2108ea 100644
--- a/go/operation/system_message_test.go
+++ b/go/weedpb/system_message_test.go
@@ -1,4 +1,4 @@
-package operation
+package weedpb
 
 import (
 	"encoding/json"
@@ -10,28 +10,28 @@ import (
 
 func TestSerialDeserial(t *testing.T) {
 	volumeMessage := &VolumeInformationMessage{
-		Id:               proto.Uint32(12),
-		Size:             proto.Uint64(2341234),
-		Collection:       proto.String("benchmark"),
-		FileCount:        proto.Uint64(2341234),
-		DeleteCount:      proto.Uint64(234),
-		DeletedByteCount: proto.Uint64(21234),
-		ReadOnly:         proto.Bool(false),
-		ReplicaPlacement: proto.Uint32(210),
-		Version:          proto.Uint32(2),
+		Id:               12,
+		Size:             2341234,
+		Collection:       "benchmark",
+		FileCount:        2341234,
+		DeleteCount:      234,
+		DeletedByteCount: 21234,
+		ReadOnly:         false,
+		ReplicaPlacement: 210,
+		Version:          2,
 	}
 	var volumeMessages []*VolumeInformationMessage
 	volumeMessages = append(volumeMessages, volumeMessage)
 
 	joinMessage := &JoinMessage{
-		IsInit:         proto.Bool(true),
-		Ip:             proto.String("127.0.3.12"),
-		Port:           proto.Uint32(34546),
-		PublicUrl:      proto.String("localhost:2342"),
-		MaxVolumeCount: proto.Uint32(210),
-		MaxFileKey:     proto.Uint64(324234423),
-		DataCenter:     proto.String("dc1"),
-		Rack:           proto.String("rack2"),
+		IsInit:         true,
+		Ip:             "127.0.3.12",
+		Port:           34546,
+		PublicUrl:      "localhost:2342",
+		MaxVolumeCount: 210,
+		MaxFileKey:     324234423,
+		DataCenter:     "dc1",
+		Rack:           "rack2",
 		Volumes:        volumeMessages,
 	}
 
@@ -53,7 +53,7 @@ func TestSerialDeserial(t *testing.T) {
 	log.Println("The json data size is", len(jsonData), string(jsonData))
 
 	// Now test and newTest contain the same data.
-	if *joinMessage.PublicUrl != *newMessage.PublicUrl {
-		log.Fatalf("data mismatch %q != %q", *joinMessage.PublicUrl, *newMessage.PublicUrl)
+	if joinMessage.PublicUrl != newMessage.PublicUrl {
+		log.Fatalf("data mismatch %q != %q", joinMessage.PublicUrl, newMessage.PublicUrl)
 	}
 }