diff --git a/go/operation/list_masters.go b/go/operation/list_masters.go
new file mode 100644
index 000000000..05235aed0
--- /dev/null
+++ b/go/operation/list_masters.go
@@ -0,0 +1,27 @@
+package operation
+
+import (
+	"code.google.com/p/weed-fs/go/glog"
+	"code.google.com/p/weed-fs/go/util"
+	"encoding/json"
+)
+
+type ClusterStatusResult struct {
+	IsLeader bool
+	Leader   string
+	Peers    []string
+}
+
+func ListMasters(server string) ([]string, error) {
+	jsonBlob, err := util.Get("http://" + server + "/cluster/status")
+	glog.V(2).Info("list masters result :", string(jsonBlob))
+	if err != nil {
+		return nil, err
+	}
+	var ret ClusterStatusResult
+	err = json.Unmarshal(jsonBlob, &ret)
+	if err != nil {
+		return nil, err
+	}
+	return ret.Peers, nil
+}
diff --git a/go/operation/lookup_volume_id.go b/go/operation/lookup_volume_id.go
index cd1d3b1bd..6e6035fae 100644
--- a/go/operation/lookup_volume_id.go
+++ b/go/operation/lookup_volume_id.go
@@ -1,12 +1,12 @@
 package operation
 
 import (
-	"code.google.com/p/weed-fs/go/storage"
 	"code.google.com/p/weed-fs/go/util"
 	"encoding/json"
 	"errors"
 	_ "fmt"
 	"net/url"
+	"strings"
 )
 
 type Location struct {
@@ -18,9 +18,9 @@ type LookupResult struct {
 	Error     string     `json:"error"`
 }
 
-func Lookup(server string, vid storage.VolumeId) (*LookupResult, error) {
+func Lookup(server string, vid string) (*LookupResult, error) {
 	values := make(url.Values)
-	values.Add("volumeId", vid.String())
+	values.Add("volumeId", vid)
 	jsonBlob, err := util.Post("http://"+server+"/dir/lookup", values)
 	if err != nil {
 		return nil, err
@@ -37,11 +37,11 @@ func Lookup(server string, vid storage.VolumeId) (*LookupResult, error) {
 }
 
 func LookupFileId(server string, fileId string) (fullUrl string, err error) {
-	fid, parseErr := storage.ParseFileId(fileId)
-	if parseErr != nil {
-		return "", parseErr
+	a := strings.Split(fileId, ",")
+	if len(a) != 2 {
+		return "", errors.New("Invalid fileId " + fileId)
 	}
-	lookup, lookupError := Lookup(server, fid.VolumeId)
+	lookup, lookupError := Lookup(server, a[0])
 	if lookupError != nil {
 		return "", lookupError
 	}
diff --git a/go/operation/allocate_volume.go b/go/replication/allocate_volume.go
similarity index 97%
rename from go/operation/allocate_volume.go
rename to go/replication/allocate_volume.go
index 3f96583e5..0f5ebc00f 100644
--- a/go/operation/allocate_volume.go
+++ b/go/replication/allocate_volume.go
@@ -1,4 +1,4 @@
-package operation
+package replication
 
 import (
 	"code.google.com/p/weed-fs/go/storage"
diff --git a/go/replication/store_replicate.go b/go/replication/store_replicate.go
index bc630c5d1..3e709de44 100644
--- a/go/replication/store_replicate.go
+++ b/go/replication/store_replicate.go
@@ -71,7 +71,7 @@ func ReplicatedDelete(masterNode string, store *storage.Store, volumeId storage.
 }
 
 func distributedOperation(masterNode string, store *storage.Store, volumeId storage.VolumeId, op func(location operation.Location) bool) bool {
-	if lookupResult, lookupErr := operation.Lookup(masterNode, volumeId); lookupErr == nil {
+	if lookupResult, lookupErr := operation.Lookup(masterNode, volumeId.String()); lookupErr == nil {
 		length := 0
 		selfUrl := (store.Ip + ":" + strconv.Itoa(store.Port))
 		results := make(chan bool)
diff --git a/go/replication/volume_growth.go b/go/replication/volume_growth.go
index 6e5bf1f5c..d7d1c90bd 100644
--- a/go/replication/volume_growth.go
+++ b/go/replication/volume_growth.go
@@ -2,7 +2,6 @@ package replication
 
 import (
 	"code.google.com/p/weed-fs/go/glog"
-	"code.google.com/p/weed-fs/go/operation"
 	"code.google.com/p/weed-fs/go/storage"
 	"code.google.com/p/weed-fs/go/topology"
 	"errors"
@@ -200,7 +199,7 @@ func (vg *VolumeGrowth) GrowByCountAndType(count int, collection string, repType
 }
 func (vg *VolumeGrowth) grow(topo *topology.Topology, vid storage.VolumeId, collection string, repType storage.ReplicationType, servers ...*topology.DataNode) error {
 	for _, server := range servers {
-		if err := operation.AllocateVolume(server, vid, collection, repType); err == nil {
+		if err := AllocateVolume(server, vid, collection, repType); err == nil {
 			vi := storage.VolumeInfo{Id: vid, Size: 0, Collection: collection, RepType: repType, Version: storage.CurrentVersion}
 			server.AddOrUpdateVolume(vi)
 			topo.RegisterVolumeLayout(&vi, server)
diff --git a/go/storage/store.go b/go/storage/store.go
index 84386cd86..52e78d27d 100644
--- a/go/storage/store.go
+++ b/go/storage/store.go
@@ -2,10 +2,13 @@ package storage
 
 import (
 	"code.google.com/p/weed-fs/go/glog"
+	"code.google.com/p/weed-fs/go/operation"
 	"code.google.com/p/weed-fs/go/util"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io/ioutil"
+	"math/rand"
 	"net/url"
 	"strconv"
 	"strings"
@@ -16,16 +19,53 @@ type DiskLocation struct {
 	maxVolumeCount int
 	volumes        map[VolumeId]*Volume
 }
+type MasterNodes struct {
+	nodes    []string
+	lastNode int
+}
+
+func NewMasterNodes(bootstrapNode string) (mn *MasterNodes) {
+	mn = &MasterNodes{nodes: []string{bootstrapNode}, lastNode: -1}
+	return
+}
+func (mn *MasterNodes) reset() {
+	if len(mn.nodes) > 1 && mn.lastNode > 0 {
+		mn.lastNode = -mn.lastNode
+	}
+}
+func (mn *MasterNodes) findMaster() (string, error) {
+	if len(mn.nodes) == 0 {
+		return "", errors.New("No master node found!")
+	}
+	if mn.lastNode < 0 {
+		for _, m := range mn.nodes {
+			if masters, e := operation.ListMasters(m); e == nil {
+				mn.nodes = masters
+				mn.lastNode = rand.Intn(len(mn.nodes))
+				glog.V(2).Info("current master node is :", mn.nodes[mn.lastNode])
+				break
+			}
+		}
+	}
+	if len(mn.nodes) == 1 {
+		return mn.nodes[0], nil
+	}
+	if mn.lastNode < 0 {
+		return "", errors.New("No master node avalable!")
+	}
+	return mn.nodes[mn.lastNode], nil
+}
+
 type Store struct {
 	Port            int
 	Ip              string
 	PublicUrl       string
 	locations       []*DiskLocation
-	masterNode      string
 	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
 }
 
 func NewStore(port int, ip, publicUrl string, dirnames []string, maxVolumeCounts []int) (s *Store) {
@@ -199,16 +239,21 @@ type JoinResult struct {
 	VolumeSizeLimit uint64
 }
 
-func (s *Store) SetMaster(mserver string) {
-	s.masterNode = mserver
-}
 func (s *Store) SetDataCenter(dataCenter string) {
 	s.dataCenter = dataCenter
 }
 func (s *Store) SetRack(rack string) {
 	s.rack = rack
 }
+
+func (s *Store) SetBootstrapMaster(bootstrapMaster string) {
+	s.masterNodes = NewMasterNodes(bootstrapMaster)
+}
 func (s *Store) Join() error {
+	masterNode, e := s.masterNodes.findMaster()
+	if e != nil {
+		return e
+	}
 	stats := new([]*VolumeInfo)
 	maxVolumeCount := 0
 	for _, location := range s.locations {
@@ -237,8 +282,9 @@ func (s *Store) Join() error {
 	values.Add("maxVolumeCount", strconv.Itoa(maxVolumeCount))
 	values.Add("dataCenter", s.dataCenter)
 	values.Add("rack", s.rack)
-	jsonBlob, err := util.Post("http://"+s.masterNode+"/dir/join", values)
+	jsonBlob, err := util.Post("http://"+masterNode+"/dir/join", values)
 	if err != nil {
+		s.masterNodes.reset()
 		return err
 	}
 	var ret JoinResult
diff --git a/go/util/post.go b/go/util/http_util.go
similarity index 58%
rename from go/util/post.go
rename to go/util/http_util.go
index cbc6dcfd5..80589dcfa 100644
--- a/go/util/post.go
+++ b/go/util/http_util.go
@@ -21,3 +21,18 @@ func Post(url string, values url.Values) ([]byte, error) {
 	}
 	return b, nil
 }
+
+func Get(url string) ([]byte, error) {
+	r, err := http.Get(url)
+	if err != nil {
+		glog.V(0).Infoln("getting ", url, err)
+		return nil, err
+	}
+	defer r.Body.Close()
+	b, err := ioutil.ReadAll(r.Body)
+	if err != nil {
+		glog.V(0).Infoln("read get result from", url, err)
+		return nil, err
+	}
+	return b, nil
+}
diff --git a/go/weed/master.go b/go/weed/master.go
index 146974166..97def1948 100644
--- a/go/weed/master.go
+++ b/go/weed/master.go
@@ -28,8 +28,9 @@ var cmdMaster = &Command{
 
 var (
 	mport                 = cmdMaster.Flag.Int("port", 9333, "http listen port")
-	mip                   = cmdMaster.Flag.String("ip", "localhost", "http listen port")
+	masterIp              = cmdMaster.Flag.String("ip", "", "master ip address")
 	metaFolder            = cmdMaster.Flag.String("mdir", os.TempDir(), "data directory to store meta data")
+	masterPeers           = cmdMaster.Flag.String("peers", "", "other master nodes in comma separated ip:port list")
 	volumeSizeLimitMB     = cmdMaster.Flag.Uint("volumeSizeLimitMB", 32*1000, "Default Volume Size in MegaBytes")
 	mpulse                = cmdMaster.Flag.Int("pulseSeconds", 5, "number of seconds between heartbeats")
 	confFile              = cmdMaster.Flag.String("conf", "/etc/weedfs/weedfs.conf", "xml configuration file")
@@ -55,16 +56,28 @@ func runMaster(cmd *Command, args []string) bool {
 	}
 
 	r := mux.NewRouter()
-	weed_server.NewMasterServer(r, VERSION, *mport, *metaFolder,
+	ms := weed_server.NewMasterServer(r, VERSION, *mport, *metaFolder,
 		*volumeSizeLimitMB, *mpulse, *confFile, *defaultRepType, *garbageThreshold, masterWhiteList,
 	)
 
-	glog.V(0).Infoln("Start Weed Master", VERSION, "at port", *mip+":"+strconv.Itoa(*mport))
+	glog.V(0).Infoln("Start Weed Master", VERSION, "at port", *masterIp+":"+strconv.Itoa(*mport))
+
 	srv := &http.Server{
-		Addr:        *mip + ":" + strconv.Itoa(*mport),
+		Addr:        *masterIp + ":" + strconv.Itoa(*mport),
 		Handler:     r,
 		ReadTimeout: time.Duration(*mReadTimeout) * time.Second,
 	}
+
+	go func() {
+		time.Sleep(100 * time.Millisecond)
+		var peers []string
+		if *masterPeers != "" {
+			peers = strings.Split(*masterPeers, ",")
+		}
+		raftServer := weed_server.NewRaftServer(r, VERSION, peers, *masterIp+":"+strconv.Itoa(*mport), *metaFolder)
+		ms.SetRaftServer(raftServer)
+	}()
+
 	e := srv.ListenAndServe()
 	if e != nil {
 		glog.Fatalf("Fail to start:%s", e)
diff --git a/go/weed/weed_server/volume_server.go b/go/weed/weed_server/volume_server.go
index 732097bde..f42585da2 100644
--- a/go/weed/weed_server/volume_server.go
+++ b/go/weed/weed_server/volume_server.go
@@ -43,7 +43,7 @@ func NewVolumeServer(r *http.ServeMux, version string, ip string, port int, publ
 
 	go func() {
 		connected := true
-		vs.store.SetMaster(vs.masterNode)
+		vs.store.SetBootstrapMaster(vs.masterNode)
 		vs.store.SetDataCenter(vs.dataCenter)
 		vs.store.SetRack(vs.rack)
 		for {
@@ -58,7 +58,11 @@ func NewVolumeServer(r *http.ServeMux, version string, ip string, port int, publ
 					connected = false
 				}
 			}
-			time.Sleep(time.Duration(float32(vs.pulseSeconds*1e3)*(1+rand.Float32())) * time.Millisecond)
+			if connected {
+				time.Sleep(time.Duration(float32(vs.pulseSeconds*1e3)*(1+rand.Float32())) * time.Millisecond)
+			} else {
+				time.Sleep(time.Duration(float32(vs.pulseSeconds*1e3)* 0.25) * time.Millisecond)
+			}
 		}
 	}()
 	glog.V(0).Infoln("store joined at", vs.masterNode)
diff --git a/go/weed/weed_server/volume_server_handlers.go b/go/weed/weed_server/volume_server_handlers.go
index c7671fe37..2f4673763 100644
--- a/go/weed/weed_server/volume_server_handlers.go
+++ b/go/weed/weed_server/volume_server_handlers.go
@@ -102,7 +102,7 @@ func (vs *VolumeServer) GetOrHeadHandler(w http.ResponseWriter, r *http.Request,
 
 	glog.V(2).Infoln("volume", volumeId, "reading", n)
 	if !vs.store.HasVolume(volumeId) {
-		lookupResult, err := operation.Lookup(vs.masterNode, volumeId)
+		lookupResult, err := operation.Lookup(vs.masterNode, volumeId.String())
 		glog.V(2).Infoln("volume", volumeId, "found on", lookupResult, "error", err)
 		if err == nil && len(lookupResult.Locations) > 0 {
 			http.Redirect(w, r, "http://"+lookupResult.Locations[0].PublicUrl+r.URL.Path, http.StatusMovedPermanently)