diff --git a/go.mod b/go.mod
index 8fab3bb84..48879fd8c 100644
--- a/go.mod
+++ b/go.mod
@@ -69,7 +69,7 @@ require (
 	github.com/spf13/jwalterweatherman v1.1.0 // indirect
 	github.com/spf13/viper v1.4.0
 	github.com/streadway/amqp v0.0.0-20190827072141-edfb9018d271 // indirect
-	github.com/stretchr/testify v1.4.0 // indirect
+	github.com/stretchr/testify v1.4.0
 	github.com/syndtr/goleveldb v1.0.0
 	github.com/tidwall/gjson v1.3.2
 	github.com/tidwall/match v1.0.1
diff --git a/unmaintained/repeated_vacuum/repeated_vacuum.go b/unmaintained/repeated_vacuum/repeated_vacuum.go
index 28bcabb9b..718b6faa1 100644
--- a/unmaintained/repeated_vacuum/repeated_vacuum.go
+++ b/unmaintained/repeated_vacuum/repeated_vacuum.go
@@ -7,10 +7,8 @@ import (
 	"log"
 	"math/rand"
 
-	"github.com/chrislusf/seaweedfs/weed/security"
-	"github.com/spf13/viper"
-
 	"github.com/chrislusf/seaweedfs/weed/operation"
+	"github.com/chrislusf/seaweedfs/weed/security"
 	"github.com/chrislusf/seaweedfs/weed/util"
 )
 
@@ -23,7 +21,7 @@ func main() {
 	flag.Parse()
 
 	util.LoadConfiguration("security", false)
-	grpcDialOption := security.LoadClientTLS(viper.Sub("grpc"), "client")
+	grpcDialOption := security.LoadClientTLS(util.GetViper(), "grpc.client")
 
 	for i := 0; i < *repeat; i++ {
 		assignResult, err := operation.Assign(*master, grpcDialOption, &operation.VolumeAssignRequest{Count: 1})
diff --git a/unmaintained/volume_tailer/volume_tailer.go b/unmaintained/volume_tailer/volume_tailer.go
index f0ef51c09..3c2d36d22 100644
--- a/unmaintained/volume_tailer/volume_tailer.go
+++ b/unmaintained/volume_tailer/volume_tailer.go
@@ -25,7 +25,7 @@ func main() {
 	flag.Parse()
 
 	util2.LoadConfiguration("security", false)
-	grpcDialOption := security.LoadClientTLS(viper.Sub("grpc"), "client")
+	grpcDialOption := security.LoadClientTLS(util.GetViper(), "grpc.client")
 
 	vid := needle.VolumeId(*volumeId)
 
diff --git a/weed/command/backup.go b/weed/command/backup.go
index 0f6bed225..eb2b5ba4a 100644
--- a/weed/command/backup.go
+++ b/weed/command/backup.go
@@ -3,8 +3,6 @@ package command
 import (
 	"fmt"
 
-	"github.com/spf13/viper"
-
 	"github.com/chrislusf/seaweedfs/weed/security"
 	"github.com/chrislusf/seaweedfs/weed/storage/needle"
 	"github.com/chrislusf/seaweedfs/weed/storage/super_block"
@@ -66,7 +64,7 @@ var cmdBackup = &Command{
 func runBackup(cmd *Command, args []string) bool {
 
 	util.LoadConfiguration("security", false)
-	grpcDialOption := security.LoadClientTLS(viper.Sub("grpc"), "client")
+	grpcDialOption := security.LoadClientTLS(util.GetViper(), "grpc.client")
 
 	if *s.volumeId == -1 {
 		return false
diff --git a/weed/command/benchmark.go b/weed/command/benchmark.go
index 26be1fe3a..382e7c850 100644
--- a/weed/command/benchmark.go
+++ b/weed/command/benchmark.go
@@ -15,7 +15,6 @@ import (
 	"sync"
 	"time"
 
-	"github.com/spf13/viper"
 	"google.golang.org/grpc"
 
 	"github.com/chrislusf/seaweedfs/weed/glog"
@@ -109,7 +108,7 @@ var (
 func runBenchmark(cmd *Command, args []string) bool {
 
 	util.LoadConfiguration("security", false)
-	b.grpcDialOption = security.LoadClientTLS(viper.Sub("grpc"), "client")
+	b.grpcDialOption = security.LoadClientTLS(util.GetViper(), "grpc.client")
 
 	fmt.Printf("This is SeaweedFS version %s %s %s\n", util.VERSION, runtime.GOOS, runtime.GOARCH)
 	if *b.maxCpu < 1 {
diff --git a/weed/command/filer.go b/weed/command/filer.go
index b1ceb46f5..ea8392fac 100644
--- a/weed/command/filer.go
+++ b/weed/command/filer.go
@@ -6,14 +6,13 @@ import (
 	"strings"
 	"time"
 
-	"github.com/chrislusf/seaweedfs/weed/security"
-	"github.com/spf13/viper"
+	"google.golang.org/grpc/reflection"
 
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
+	"github.com/chrislusf/seaweedfs/weed/security"
 	"github.com/chrislusf/seaweedfs/weed/server"
 	"github.com/chrislusf/seaweedfs/weed/util"
-	"google.golang.org/grpc/reflection"
 )
 
 var (
@@ -145,7 +144,7 @@ func (fo *FilerOptions) startFiler() {
 	if err != nil {
 		glog.Fatalf("failed to listen on grpc port %d: %v", grpcPort, err)
 	}
-	grpcS := util.NewGrpcServer(security.LoadServerTLS(viper.Sub("grpc"), "filer"))
+	grpcS := util.NewGrpcServer(security.LoadServerTLS(util.GetViper(), "grpc.filer"))
 	filer_pb.RegisterSeaweedFilerServer(grpcS, fs)
 	reflection.Register(grpcS)
 	go grpcS.Serve(grpcL)
diff --git a/weed/command/filer_copy.go b/weed/command/filer_copy.go
index e74ea7d93..e5979d786 100644
--- a/weed/command/filer_copy.go
+++ b/weed/command/filer_copy.go
@@ -14,13 +14,13 @@ import (
 	"sync"
 	"time"
 
+	"google.golang.org/grpc"
+
 	"github.com/chrislusf/seaweedfs/weed/operation"
 	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
 	"github.com/chrislusf/seaweedfs/weed/security"
 	"github.com/chrislusf/seaweedfs/weed/util"
 	"github.com/chrislusf/seaweedfs/weed/wdclient"
-	"github.com/spf13/viper"
-	"google.golang.org/grpc"
 )
 
 var (
@@ -105,7 +105,7 @@ func runCopy(cmd *Command, args []string) bool {
 
 	filerGrpcPort := filerPort + 10000
 	filerGrpcAddress := fmt.Sprintf("%s:%d", filerUrl.Hostname(), filerGrpcPort)
-	copy.grpcDialOption = security.LoadClientTLS(viper.Sub("grpc"), "client")
+	copy.grpcDialOption = security.LoadClientTLS(util.GetViper(), "grpc.client")
 
 	ctx := context.Background()
 
diff --git a/weed/command/filer_replication.go b/weed/command/filer_replication.go
index c6e7f5dba..737f0d24a 100644
--- a/weed/command/filer_replication.go
+++ b/weed/command/filer_replication.go
@@ -39,7 +39,7 @@ func runFilerReplicate(cmd *Command, args []string) bool {
 	util.LoadConfiguration("security", false)
 	util.LoadConfiguration("replication", true)
 	util.LoadConfiguration("notification", true)
-	config := viper.GetViper()
+	config := util.GetViper()
 
 	var notificationInput sub.NotificationInput
 
@@ -47,8 +47,7 @@ func runFilerReplicate(cmd *Command, args []string) bool {
 
 	for _, input := range sub.NotificationInputs {
 		if config.GetBool("notification." + input.GetName() + ".enabled") {
-			viperSub := config.Sub("notification." + input.GetName())
-			if err := input.Initialize(viperSub); err != nil {
+			if err := input.Initialize(config, "notification."+input.GetName()+"."); err != nil {
 				glog.Fatalf("Failed to initialize notification input for %s: %+v",
 					input.GetName(), err)
 			}
@@ -66,10 +65,9 @@ func runFilerReplicate(cmd *Command, args []string) bool {
 
 	// avoid recursive replication
 	if config.GetBool("notification.source.filer.enabled") && config.GetBool("notification.sink.filer.enabled") {
-		sourceConfig, sinkConfig := config.Sub("source.filer"), config.Sub("sink.filer")
-		if sourceConfig.GetString("grpcAddress") == sinkConfig.GetString("grpcAddress") {
-			fromDir := sourceConfig.GetString("directory")
-			toDir := sinkConfig.GetString("directory")
+		if config.GetString("source.filer.grpcAddress") == config.GetString("sink.filer.grpcAddress") {
+			fromDir := config.GetString("source.filer.directory")
+			toDir := config.GetString("sink.filer.directory")
 			if strings.HasPrefix(toDir, fromDir) {
 				glog.Fatalf("recursive replication! source directory %s includes the sink directory %s", fromDir, toDir)
 			}
@@ -79,8 +77,7 @@ func runFilerReplicate(cmd *Command, args []string) bool {
 	var dataSink sink.ReplicationSink
 	for _, sk := range sink.Sinks {
 		if config.GetBool("sink." + sk.GetName() + ".enabled") {
-			viperSub := config.Sub("sink." + sk.GetName())
-			if err := sk.Initialize(viperSub); err != nil {
+			if err := sk.Initialize(config, "sink."+sk.GetName()+"."); err != nil {
 				glog.Fatalf("Failed to initialize sink for %s: %+v",
 					sk.GetName(), err)
 			}
@@ -98,7 +95,7 @@ func runFilerReplicate(cmd *Command, args []string) bool {
 		return true
 	}
 
-	replicator := replication.NewReplicator(config.Sub("source.filer"), dataSink)
+	replicator := replication.NewReplicator(config, "source.filer.", dataSink)
 
 	for {
 		key, m, err := notificationInput.ReceiveMessage()
diff --git a/weed/command/master.go b/weed/command/master.go
index 8d0a3289c..c4b11119b 100644
--- a/weed/command/master.go
+++ b/weed/command/master.go
@@ -8,15 +8,15 @@ import (
 	"strings"
 
 	"github.com/chrislusf/raft/protobuf"
+	"github.com/gorilla/mux"
+	"google.golang.org/grpc/reflection"
+
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/pb/master_pb"
 	"github.com/chrislusf/seaweedfs/weed/security"
 	"github.com/chrislusf/seaweedfs/weed/server"
 	"github.com/chrislusf/seaweedfs/weed/storage/backend"
 	"github.com/chrislusf/seaweedfs/weed/util"
-	"github.com/gorilla/mux"
-	"github.com/spf13/viper"
-	"google.golang.org/grpc/reflection"
 )
 
 var (
@@ -102,7 +102,7 @@ func runMaster(cmd *Command, args []string) bool {
 
 func startMaster(masterOption MasterOptions, masterWhiteList []string) {
 
-	backend.LoadConfiguration(viper.GetViper())
+	backend.LoadConfiguration(util.GetViper())
 
 	myMasterAddress, peers := checkPeers(*masterOption.ip, *masterOption.port, *masterOption.peers)
 
@@ -115,7 +115,7 @@ func startMaster(masterOption MasterOptions, masterWhiteList []string) {
 		glog.Fatalf("Master startup error: %v", e)
 	}
 	// start raftServer
-	raftServer := weed_server.NewRaftServer(security.LoadClientTLS(viper.Sub("grpc"), "master"),
+	raftServer := weed_server.NewRaftServer(security.LoadClientTLS(util.GetViper(), "grpc.master"),
 		peers, myMasterAddress, *masterOption.metaFolder, ms.Topo, *masterOption.pulseSeconds)
 	if raftServer == nil {
 		glog.Fatalf("please verify %s is writable, see https://github.com/chrislusf/seaweedfs/issues/717", *masterOption.metaFolder)
@@ -129,7 +129,7 @@ func startMaster(masterOption MasterOptions, masterWhiteList []string) {
 		glog.Fatalf("master failed to listen on grpc port %d: %v", grpcPort, err)
 	}
 	// Create your protocol servers.
-	grpcS := util.NewGrpcServer(security.LoadServerTLS(viper.Sub("grpc"), "master"))
+	grpcS := util.NewGrpcServer(security.LoadServerTLS(util.GetViper(), "grpc.master"))
 	master_pb.RegisterSeaweedServer(grpcS, ms)
 	protobuf.RegisterRaftServer(grpcS, raftServer)
 	reflection.Register(grpcS)
diff --git a/weed/command/mount_std.go b/weed/command/mount_std.go
index 453531d00..891810e61 100644
--- a/weed/command/mount_std.go
+++ b/weed/command/mount_std.go
@@ -13,7 +13,6 @@ import (
 	"time"
 
 	"github.com/jacobsa/daemonize"
-	"github.com/spf13/viper"
 
 	"github.com/chrislusf/seaweedfs/weed/filesys"
 	"github.com/chrislusf/seaweedfs/weed/glog"
@@ -148,7 +147,7 @@ func RunMount(filer, filerMountRootPath, dir, collection, replication, dataCente
 
 	err = fs.Serve(c, filesys.NewSeaweedFileSystem(&filesys.Option{
 		FilerGrpcAddress:   filerGrpcAddress,
-		GrpcDialOption:     security.LoadClientTLS(viper.Sub("grpc"), "client"),
+		GrpcDialOption:     security.LoadClientTLS(util.GetViper(), "grpc.client"),
 		FilerMountRootPath: mountRoot,
 		Collection:         collection,
 		Replication:        replication,
diff --git a/weed/command/s3.go b/weed/command/s3.go
index e004bb066..10a486657 100644
--- a/weed/command/s3.go
+++ b/weed/command/s3.go
@@ -1,18 +1,17 @@
 package command
 
 import (
+	"fmt"
 	"net/http"
 	"time"
 
 	"github.com/chrislusf/seaweedfs/weed/security"
-	"github.com/spf13/viper"
 
-	"fmt"
+	"github.com/gorilla/mux"
 
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/s3api"
 	"github.com/chrislusf/seaweedfs/weed/util"
-	"github.com/gorilla/mux"
 )
 
 var (
@@ -69,7 +68,7 @@ func (s3opt *S3Options) startS3Server() bool {
 		FilerGrpcAddress: filerGrpcAddress,
 		DomainName:       *s3opt.domainName,
 		BucketsPath:      *s3opt.filerBucketsPath,
-		GrpcDialOption:   security.LoadClientTLS(viper.Sub("grpc"), "client"),
+		GrpcDialOption:   security.LoadClientTLS(util.GetViper(), "grpc.client"),
 	})
 	if s3ApiServer_err != nil {
 		glog.Fatalf("S3 API Server startup error: %v", s3ApiServer_err)
diff --git a/weed/command/scaffold.go b/weed/command/scaffold.go
index 78eec277c..524bf5e13 100644
--- a/weed/command/scaffold.go
+++ b/weed/command/scaffold.go
@@ -14,6 +14,14 @@ var cmdScaffold = &Command{
 	Short:     "generate basic configuration files",
 	Long: `Generate filer.toml with all possible configurations for you to customize.
 
+	The options can also be overwritten by environment variables.
+	For example, the filer.toml mysql password can be overwritten by environment variable
+		export weed.mysql.password=some_password
+	Environment variable rules:
+		* Prefix fix with "WEED_"
+		* Upppercase the reset of variable name.
+		* Replace '.' with '_'
+
   `,
 }
 
diff --git a/weed/command/shell.go b/weed/command/shell.go
index 34b5aef31..dcf70608f 100644
--- a/weed/command/shell.go
+++ b/weed/command/shell.go
@@ -6,7 +6,6 @@ import (
 	"github.com/chrislusf/seaweedfs/weed/security"
 	"github.com/chrislusf/seaweedfs/weed/shell"
 	"github.com/chrislusf/seaweedfs/weed/util"
-	"github.com/spf13/viper"
 )
 
 var (
@@ -31,7 +30,7 @@ var cmdShell = &Command{
 func runShell(command *Command, args []string) bool {
 
 	util.LoadConfiguration("security", false)
-	shellOptions.GrpcDialOption = security.LoadClientTLS(viper.Sub("grpc"), "client")
+	shellOptions.GrpcDialOption = security.LoadClientTLS(util.GetViper(), "grpc.client")
 
 	var filerPwdErr error
 	shellOptions.FilerHost, shellOptions.FilerPort, shellOptions.Directory, filerPwdErr = util.ParseFilerUrl(*shellInitialFilerUrl)
diff --git a/weed/command/upload.go b/weed/command/upload.go
index 25e938d9b..d71046131 100644
--- a/weed/command/upload.go
+++ b/weed/command/upload.go
@@ -6,11 +6,9 @@ import (
 	"os"
 	"path/filepath"
 
+	"github.com/chrislusf/seaweedfs/weed/operation"
 	"github.com/chrislusf/seaweedfs/weed/security"
 	"github.com/chrislusf/seaweedfs/weed/util"
-	"github.com/spf13/viper"
-
-	"github.com/chrislusf/seaweedfs/weed/operation"
 )
 
 var (
@@ -63,7 +61,7 @@ var cmdUpload = &Command{
 func runUpload(cmd *Command, args []string) bool {
 
 	util.LoadConfiguration("security", false)
-	grpcDialOption := security.LoadClientTLS(viper.Sub("grpc"), "client")
+	grpcDialOption := security.LoadClientTLS(util.GetViper(), "grpc.client")
 
 	if len(args) == 0 {
 		if *upload.dir == "" {
diff --git a/weed/command/volume.go b/weed/command/volume.go
index b0f46bbf3..9d665d143 100644
--- a/weed/command/volume.go
+++ b/weed/command/volume.go
@@ -234,7 +234,7 @@ func (v VolumeServerOptions) startGrpcService(vs volume_server_pb.VolumeServerSe
 	if err != nil {
 		glog.Fatalf("failed to listen on grpc port %d: %v", grpcPort, err)
 	}
-	grpcS := util.NewGrpcServer(security.LoadServerTLS(viper.Sub("grpc"), "volume"))
+	grpcS := util.NewGrpcServer(security.LoadServerTLS(util.GetViper(), "grpc.volume"))
 	volume_server_pb.RegisterVolumeServerServer(grpcS, vs)
 	reflection.Register(grpcS)
 	go func() {
diff --git a/weed/command/webdav.go b/weed/command/webdav.go
index 371c4a9ad..0e6f89040 100644
--- a/weed/command/webdav.go
+++ b/weed/command/webdav.go
@@ -11,7 +11,6 @@ import (
 	"github.com/chrislusf/seaweedfs/weed/security"
 	"github.com/chrislusf/seaweedfs/weed/server"
 	"github.com/chrislusf/seaweedfs/weed/util"
-	"github.com/spf13/viper"
 )
 
 var (
@@ -75,7 +74,7 @@ func (wo *WebDavOption) startWebDav() bool {
 	ws, webdavServer_err := weed_server.NewWebDavServer(&weed_server.WebDavOption{
 		Filer:            *wo.filer,
 		FilerGrpcAddress: filerGrpcAddress,
-		GrpcDialOption:   security.LoadClientTLS(viper.Sub("grpc"), "client"),
+		GrpcDialOption:   security.LoadClientTLS(util.GetViper(), "grpc.client"),
 		Collection:       *wo.collection,
 		Uid:              uid,
 		Gid:              gid,
diff --git a/weed/filer2/cassandra/cassandra_store.go b/weed/filer2/cassandra/cassandra_store.go
index dcaab8bc4..f81ef946f 100644
--- a/weed/filer2/cassandra/cassandra_store.go
+++ b/weed/filer2/cassandra/cassandra_store.go
@@ -22,10 +22,10 @@ func (store *CassandraStore) GetName() string {
 	return "cassandra"
 }
 
-func (store *CassandraStore) Initialize(configuration util.Configuration) (err error) {
+func (store *CassandraStore) Initialize(configuration util.Configuration, prefix string) (err error) {
 	return store.initialize(
-		configuration.GetString("keyspace"),
-		configuration.GetStringSlice("hosts"),
+		configuration.GetString(prefix+"keyspace"),
+		configuration.GetStringSlice(prefix+"hosts"),
 	)
 }
 
diff --git a/weed/filer2/configuration.go b/weed/filer2/configuration.go
index 7b05b53dc..a174117ea 100644
--- a/weed/filer2/configuration.go
+++ b/weed/filer2/configuration.go
@@ -17,8 +17,7 @@ func (f *Filer) LoadConfiguration(config *viper.Viper) {
 
 	for _, store := range Stores {
 		if config.GetBool(store.GetName() + ".enabled") {
-			viperSub := config.Sub(store.GetName())
-			if err := store.Initialize(viperSub); err != nil {
+			if err := store.Initialize(config, store.GetName()+"."); err != nil {
 				glog.Fatalf("Failed to initialize store for %s: %+v",
 					store.GetName(), err)
 			}
diff --git a/weed/filer2/etcd/etcd_store.go b/weed/filer2/etcd/etcd_store.go
index 2eb9e3e86..0f0c01426 100644
--- a/weed/filer2/etcd/etcd_store.go
+++ b/weed/filer2/etcd/etcd_store.go
@@ -28,13 +28,13 @@ func (store *EtcdStore) GetName() string {
 	return "etcd"
 }
 
-func (store *EtcdStore) Initialize(configuration weed_util.Configuration) (err error) {
-	servers := configuration.GetString("servers")
+func (store *EtcdStore) Initialize(configuration weed_util.Configuration, prefix string) (err error) {
+	servers := configuration.GetString(prefix + "servers")
 	if servers == "" {
 		servers = "localhost:2379"
 	}
 
-	timeout := configuration.GetString("timeout")
+	timeout := configuration.GetString(prefix + "timeout")
 	if timeout == "" {
 		timeout = "3s"
 	}
diff --git a/weed/filer2/filechunks_test.go b/weed/filer2/filechunks_test.go
index ed30c2abc..bb4a6c74d 100644
--- a/weed/filer2/filechunks_test.go
+++ b/weed/filer2/filechunks_test.go
@@ -350,21 +350,21 @@ func TestChunksReading(t *testing.T) {
 		{
 			Chunks: []*filer_pb.FileChunk{
 				{Offset: 0, Size: 43175947, FileId: "2,111fc2cbfac1", Mtime: 1},
-				{Offset: 43175936, Size: 52981771-43175936, FileId: "2,112a36ea7f85", Mtime: 2},
-				{Offset: 52981760, Size: 72564747-52981760, FileId: "4,112d5f31c5e7", Mtime: 3},
-				{Offset: 72564736, Size: 133255179-72564736, FileId: "1,113245f0cdb6", Mtime: 4},
-				{Offset: 133255168, Size: 137269259-133255168, FileId: "3,1141a70733b5", Mtime: 5},
-				{Offset: 137269248, Size: 153578836-137269248, FileId: "1,114201d5bbdb", Mtime: 6},
+				{Offset: 43175936, Size: 52981771 - 43175936, FileId: "2,112a36ea7f85", Mtime: 2},
+				{Offset: 52981760, Size: 72564747 - 52981760, FileId: "4,112d5f31c5e7", Mtime: 3},
+				{Offset: 72564736, Size: 133255179 - 72564736, FileId: "1,113245f0cdb6", Mtime: 4},
+				{Offset: 133255168, Size: 137269259 - 133255168, FileId: "3,1141a70733b5", Mtime: 5},
+				{Offset: 137269248, Size: 153578836 - 137269248, FileId: "1,114201d5bbdb", Mtime: 6},
 			},
 			Offset: 0,
 			Size:   153578836,
 			Expected: []*ChunkView{
 				{Offset: 0, Size: 43175936, FileId: "2,111fc2cbfac1", LogicOffset: 0},
-				{Offset: 0, Size: 52981760-43175936, FileId: "2,112a36ea7f85", LogicOffset: 43175936},
-				{Offset: 0, Size: 72564736-52981760, FileId: "4,112d5f31c5e7", LogicOffset: 52981760},
-				{Offset: 0, Size: 133255168-72564736, FileId: "1,113245f0cdb6", LogicOffset: 72564736},
-				{Offset: 0, Size: 137269248-133255168, FileId: "3,1141a70733b5", LogicOffset: 133255168},
-				{Offset: 0, Size: 153578836-137269248, FileId: "1,114201d5bbdb", LogicOffset: 137269248},
+				{Offset: 0, Size: 52981760 - 43175936, FileId: "2,112a36ea7f85", LogicOffset: 43175936},
+				{Offset: 0, Size: 72564736 - 52981760, FileId: "4,112d5f31c5e7", LogicOffset: 52981760},
+				{Offset: 0, Size: 133255168 - 72564736, FileId: "1,113245f0cdb6", LogicOffset: 72564736},
+				{Offset: 0, Size: 137269248 - 133255168, FileId: "3,1141a70733b5", LogicOffset: 133255168},
+				{Offset: 0, Size: 153578836 - 137269248, FileId: "1,114201d5bbdb", LogicOffset: 137269248},
 			},
 		},
 	}
diff --git a/weed/filer2/filerstore.go b/weed/filer2/filerstore.go
index 0bb0bd611..ae25534ed 100644
--- a/weed/filer2/filerstore.go
+++ b/weed/filer2/filerstore.go
@@ -14,7 +14,7 @@ type FilerStore interface {
 	// GetName gets the name to locate the configuration in filer.toml file
 	GetName() string
 	// Initialize initializes the file store
-	Initialize(configuration util.Configuration) error
+	Initialize(configuration util.Configuration, prefix string) error
 	InsertEntry(context.Context, *Entry) error
 	UpdateEntry(context.Context, *Entry) (err error)
 	// err == filer2.ErrNotFound if not found
@@ -47,8 +47,8 @@ func (fsw *FilerStoreWrapper) GetName() string {
 	return fsw.actualStore.GetName()
 }
 
-func (fsw *FilerStoreWrapper) Initialize(configuration util.Configuration) error {
-	return fsw.actualStore.Initialize(configuration)
+func (fsw *FilerStoreWrapper) Initialize(configuration util.Configuration, prefix string) error {
+	return fsw.actualStore.Initialize(configuration, prefix)
 }
 
 func (fsw *FilerStoreWrapper) InsertEntry(ctx context.Context, entry *Entry) error {
diff --git a/weed/filer2/leveldb/leveldb_store.go b/weed/filer2/leveldb/leveldb_store.go
index 4952b3b3a..44e6ac0eb 100644
--- a/weed/filer2/leveldb/leveldb_store.go
+++ b/weed/filer2/leveldb/leveldb_store.go
@@ -30,8 +30,8 @@ func (store *LevelDBStore) GetName() string {
 	return "leveldb"
 }
 
-func (store *LevelDBStore) Initialize(configuration weed_util.Configuration) (err error) {
-	dir := configuration.GetString("dir")
+func (store *LevelDBStore) Initialize(configuration weed_util.Configuration, prefix string) (err error) {
+	dir := configuration.GetString(prefix + "dir")
 	return store.initialize(dir)
 }
 
diff --git a/weed/filer2/leveldb2/leveldb2_store.go b/weed/filer2/leveldb2/leveldb2_store.go
index 8a16822ab..358d4d92a 100644
--- a/weed/filer2/leveldb2/leveldb2_store.go
+++ b/weed/filer2/leveldb2/leveldb2_store.go
@@ -30,8 +30,8 @@ func (store *LevelDB2Store) GetName() string {
 	return "leveldb2"
 }
 
-func (store *LevelDB2Store) Initialize(configuration weed_util.Configuration) (err error) {
-	dir := configuration.GetString("dir")
+func (store *LevelDB2Store) Initialize(configuration weed_util.Configuration, prefix string) (err error) {
+	dir := configuration.GetString(prefix + "dir")
 	return store.initialize(dir, 8)
 }
 
diff --git a/weed/filer2/mysql/mysql_store.go b/weed/filer2/mysql/mysql_store.go
index d1b06ece5..63d99cd9d 100644
--- a/weed/filer2/mysql/mysql_store.go
+++ b/weed/filer2/mysql/mysql_store.go
@@ -26,16 +26,16 @@ func (store *MysqlStore) GetName() string {
 	return "mysql"
 }
 
-func (store *MysqlStore) Initialize(configuration util.Configuration) (err error) {
+func (store *MysqlStore) Initialize(configuration util.Configuration, prefix string) (err error) {
 	return store.initialize(
-		configuration.GetString("username"),
-		configuration.GetString("password"),
-		configuration.GetString("hostname"),
-		configuration.GetInt("port"),
-		configuration.GetString("database"),
-		configuration.GetInt("connection_max_idle"),
-		configuration.GetInt("connection_max_open"),
-		configuration.GetBool("interpolateParams"),
+		configuration.GetString(prefix+"username"),
+		configuration.GetString(prefix+"password"),
+		configuration.GetString(prefix+"hostname"),
+		configuration.GetInt(prefix+"port"),
+		configuration.GetString(prefix+"database"),
+		configuration.GetInt(prefix+"connection_max_idle"),
+		configuration.GetInt(prefix+"connection_max_open"),
+		configuration.GetBool(prefix+"interpolateParams"),
 	)
 }
 
diff --git a/weed/filer2/postgres/postgres_store.go b/weed/filer2/postgres/postgres_store.go
index 3ec000fe0..27a0c2513 100644
--- a/weed/filer2/postgres/postgres_store.go
+++ b/weed/filer2/postgres/postgres_store.go
@@ -26,16 +26,16 @@ func (store *PostgresStore) GetName() string {
 	return "postgres"
 }
 
-func (store *PostgresStore) Initialize(configuration util.Configuration) (err error) {
+func (store *PostgresStore) Initialize(configuration util.Configuration, prefix string) (err error) {
 	return store.initialize(
-		configuration.GetString("username"),
-		configuration.GetString("password"),
-		configuration.GetString("hostname"),
-		configuration.GetInt("port"),
-		configuration.GetString("database"),
-		configuration.GetString("sslmode"),
-		configuration.GetInt("connection_max_idle"),
-		configuration.GetInt("connection_max_open"),
+		configuration.GetString(prefix+"username"),
+		configuration.GetString(prefix+"password"),
+		configuration.GetString(prefix+"hostname"),
+		configuration.GetInt(prefix+"port"),
+		configuration.GetString(prefix+"database"),
+		configuration.GetString(prefix+"sslmode"),
+		configuration.GetInt(prefix+"connection_max_idle"),
+		configuration.GetInt(prefix+"connection_max_open"),
 	)
 }
 
diff --git a/weed/filer2/redis/redis_cluster_store.go b/weed/filer2/redis/redis_cluster_store.go
index f1ad4b35c..eaaecb740 100644
--- a/weed/filer2/redis/redis_cluster_store.go
+++ b/weed/filer2/redis/redis_cluster_store.go
@@ -18,16 +18,16 @@ func (store *RedisClusterStore) GetName() string {
 	return "redis_cluster"
 }
 
-func (store *RedisClusterStore) Initialize(configuration util.Configuration) (err error) {
+func (store *RedisClusterStore) Initialize(configuration util.Configuration, prefix string) (err error) {
 
-	configuration.SetDefault("useReadOnly", true)
-	configuration.SetDefault("routeByLatency", true)
+	configuration.SetDefault(prefix+"useReadOnly", true)
+	configuration.SetDefault(prefix+"routeByLatency", true)
 
 	return store.initialize(
-		configuration.GetStringSlice("addresses"),
-		configuration.GetString("password"),
-		configuration.GetBool("useReadOnly"),
-		configuration.GetBool("routeByLatency"),
+		configuration.GetStringSlice(prefix+"addresses"),
+		configuration.GetString(prefix+"password"),
+		configuration.GetBool(prefix+"useReadOnly"),
+		configuration.GetBool(prefix+"routeByLatency"),
 	)
 }
 
diff --git a/weed/filer2/redis/redis_store.go b/weed/filer2/redis/redis_store.go
index c56fa014c..9debdb070 100644
--- a/weed/filer2/redis/redis_store.go
+++ b/weed/filer2/redis/redis_store.go
@@ -18,11 +18,11 @@ func (store *RedisStore) GetName() string {
 	return "redis"
 }
 
-func (store *RedisStore) Initialize(configuration util.Configuration) (err error) {
+func (store *RedisStore) Initialize(configuration util.Configuration, prefix string) (err error) {
 	return store.initialize(
-		configuration.GetString("address"),
-		configuration.GetString("password"),
-		configuration.GetInt("database"),
+		configuration.GetString(prefix+"address"),
+		configuration.GetString(prefix+"password"),
+		configuration.GetInt(prefix+"database"),
 	)
 }
 
diff --git a/weed/filer2/tikv/tikv_store.go b/weed/filer2/tikv/tikv_store.go
index 4eb8cb90d..24e05e3ad 100644
--- a/weed/filer2/tikv/tikv_store.go
+++ b/weed/filer2/tikv/tikv_store.go
@@ -30,8 +30,8 @@ func (store *TikvStore) GetName() string {
 	return "tikv"
 }
 
-func (store *TikvStore) Initialize(configuration weed_util.Configuration) (err error) {
-	pdAddr := configuration.GetString("pdAddress")
+func (store *TikvStore) Initialize(configuration weed_util.Configuration, prefix string) (err error) {
+	pdAddr := configuration.GetString(prefix + "pdAddress")
 	return store.initialize(pdAddr)
 }
 
diff --git a/weed/filesys/dirty_page_interval.go b/weed/filesys/dirty_page_interval.go
index 162b9be64..ec94c6df1 100644
--- a/weed/filesys/dirty_page_interval.go
+++ b/weed/filesys/dirty_page_interval.go
@@ -74,7 +74,7 @@ func subList(list *IntervalLinkedList, start, stop int64) *IntervalLinkedList {
 		nodes = append(nodes, &IntervalNode{
 			Data:   t.Data[nodeStart-t.Offset : nodeStop-t.Offset],
 			Offset: nodeStart,
-			Size:   nodeStop-nodeStart,
+			Size:   nodeStop - nodeStart,
 			Next:   nil,
 		})
 	}
diff --git a/weed/notification/aws_sqs/aws_sqs_pub.go b/weed/notification/aws_sqs/aws_sqs_pub.go
index 4c1302abb..d881049dd 100644
--- a/weed/notification/aws_sqs/aws_sqs_pub.go
+++ b/weed/notification/aws_sqs/aws_sqs_pub.go
@@ -27,14 +27,14 @@ func (k *AwsSqsPub) GetName() string {
 	return "aws_sqs"
 }
 
-func (k *AwsSqsPub) Initialize(configuration util.Configuration) (err error) {
-	glog.V(0).Infof("filer.notification.aws_sqs.region: %v", configuration.GetString("region"))
-	glog.V(0).Infof("filer.notification.aws_sqs.sqs_queue_name: %v", configuration.GetString("sqs_queue_name"))
+func (k *AwsSqsPub) Initialize(configuration util.Configuration, prefix string) (err error) {
+	glog.V(0).Infof("filer.notification.aws_sqs.region: %v", configuration.GetString(prefix+"region"))
+	glog.V(0).Infof("filer.notification.aws_sqs.sqs_queue_name: %v", configuration.GetString(prefix+"sqs_queue_name"))
 	return k.initialize(
-		configuration.GetString("aws_access_key_id"),
-		configuration.GetString("aws_secret_access_key"),
-		configuration.GetString("region"),
-		configuration.GetString("sqs_queue_name"),
+		configuration.GetString(prefix+"aws_access_key_id"),
+		configuration.GetString(prefix+"aws_secret_access_key"),
+		configuration.GetString(prefix+"region"),
+		configuration.GetString(prefix+"sqs_queue_name"),
 	)
 }
 
diff --git a/weed/notification/configuration.go b/weed/notification/configuration.go
index 7f8765cc3..36211692c 100644
--- a/weed/notification/configuration.go
+++ b/weed/notification/configuration.go
@@ -11,7 +11,7 @@ type MessageQueue interface {
 	// GetName gets the name to locate the configuration in filer.toml file
 	GetName() string
 	// Initialize initializes the file store
-	Initialize(configuration util.Configuration) error
+	Initialize(configuration util.Configuration, prefix string) error
 	SendMessage(key string, message proto.Message) error
 }
 
@@ -21,7 +21,7 @@ var (
 	Queue MessageQueue
 )
 
-func LoadConfiguration(config *viper.Viper) {
+func LoadConfiguration(config *viper.Viper, prefix string) {
 
 	if config == nil {
 		return
@@ -30,9 +30,8 @@ func LoadConfiguration(config *viper.Viper) {
 	validateOneEnabledQueue(config)
 
 	for _, queue := range MessageQueues {
-		if config.GetBool(queue.GetName() + ".enabled") {
-			viperSub := config.Sub(queue.GetName())
-			if err := queue.Initialize(viperSub); err != nil {
+		if config.GetBool(prefix + queue.GetName() + ".enabled") {
+			if err := queue.Initialize(config, prefix+queue.GetName()+"."); err != nil {
 				glog.Fatalf("Failed to initialize notification for %s: %+v",
 					queue.GetName(), err)
 			}
diff --git a/weed/notification/gocdk_pub_sub/gocdk_pub_sub.go b/weed/notification/gocdk_pub_sub/gocdk_pub_sub.go
index ebf44ea6f..706261b3a 100644
--- a/weed/notification/gocdk_pub_sub/gocdk_pub_sub.go
+++ b/weed/notification/gocdk_pub_sub/gocdk_pub_sub.go
@@ -18,12 +18,13 @@ import (
 	"context"
 	"fmt"
 
-	"github.com/chrislusf/seaweedfs/weed/glog"
-	"github.com/chrislusf/seaweedfs/weed/notification"
-	"github.com/chrislusf/seaweedfs/weed/util"
 	"github.com/golang/protobuf/proto"
 	"gocloud.dev/pubsub"
 	_ "gocloud.dev/pubsub/awssnssqs"
+
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/notification"
+	"github.com/chrislusf/seaweedfs/weed/util"
 	// _ "gocloud.dev/pubsub/azuresb"
 	_ "gocloud.dev/pubsub/gcppubsub"
 	_ "gocloud.dev/pubsub/natspubsub"
@@ -43,8 +44,8 @@ func (k *GoCDKPubSub) GetName() string {
 	return "gocdk_pub_sub"
 }
 
-func (k *GoCDKPubSub) Initialize(config util.Configuration) error {
-	k.topicURL = config.GetString("topic_url")
+func (k *GoCDKPubSub) Initialize(configuration util.Configuration, prefix string) error {
+	k.topicURL = configuration.GetString(prefix + "topic_url")
 	glog.V(0).Infof("notification.gocdk_pub_sub.topic_url: %v", k.topicURL)
 	topic, err := pubsub.OpenTopic(context.Background(), k.topicURL)
 	if err != nil {
diff --git a/weed/notification/google_pub_sub/google_pub_sub.go b/weed/notification/google_pub_sub/google_pub_sub.go
index 7b26bfe38..363a86eb6 100644
--- a/weed/notification/google_pub_sub/google_pub_sub.go
+++ b/weed/notification/google_pub_sub/google_pub_sub.go
@@ -25,13 +25,13 @@ func (k *GooglePubSub) GetName() string {
 	return "google_pub_sub"
 }
 
-func (k *GooglePubSub) Initialize(configuration util.Configuration) (err error) {
-	glog.V(0).Infof("notification.google_pub_sub.project_id: %v", configuration.GetString("project_id"))
-	glog.V(0).Infof("notification.google_pub_sub.topic: %v", configuration.GetString("topic"))
+func (k *GooglePubSub) Initialize(configuration util.Configuration, prefix string) (err error) {
+	glog.V(0).Infof("notification.google_pub_sub.project_id: %v", configuration.GetString(prefix+"project_id"))
+	glog.V(0).Infof("notification.google_pub_sub.topic: %v", configuration.GetString(prefix+"topic"))
 	return k.initialize(
-		configuration.GetString("google_application_credentials"),
-		configuration.GetString("project_id"),
-		configuration.GetString("topic"),
+		configuration.GetString(prefix+"google_application_credentials"),
+		configuration.GetString(prefix+"project_id"),
+		configuration.GetString(prefix+"topic"),
 	)
 }
 
diff --git a/weed/notification/kafka/kafka_queue.go b/weed/notification/kafka/kafka_queue.go
index fd545722b..8d83b5892 100644
--- a/weed/notification/kafka/kafka_queue.go
+++ b/weed/notification/kafka/kafka_queue.go
@@ -21,12 +21,12 @@ func (k *KafkaQueue) GetName() string {
 	return "kafka"
 }
 
-func (k *KafkaQueue) Initialize(configuration util.Configuration) (err error) {
-	glog.V(0).Infof("filer.notification.kafka.hosts: %v\n", configuration.GetStringSlice("hosts"))
-	glog.V(0).Infof("filer.notification.kafka.topic: %v\n", configuration.GetString("topic"))
+func (k *KafkaQueue) Initialize(configuration util.Configuration, prefix string) (err error) {
+	glog.V(0).Infof("filer.notification.kafka.hosts: %v\n", configuration.GetStringSlice(prefix+"hosts"))
+	glog.V(0).Infof("filer.notification.kafka.topic: %v\n", configuration.GetString(prefix+"topic"))
 	return k.initialize(
-		configuration.GetStringSlice("hosts"),
-		configuration.GetString("topic"),
+		configuration.GetStringSlice(prefix+"hosts"),
+		configuration.GetString(prefix+"topic"),
 	)
 }
 
diff --git a/weed/notification/log/log_queue.go b/weed/notification/log/log_queue.go
index dcc038dfc..1ca4786a1 100644
--- a/weed/notification/log/log_queue.go
+++ b/weed/notification/log/log_queue.go
@@ -18,7 +18,7 @@ func (k *LogQueue) GetName() string {
 	return "log"
 }
 
-func (k *LogQueue) Initialize(configuration util.Configuration) (err error) {
+func (k *LogQueue) Initialize(configuration util.Configuration, prefix string) (err error) {
 	return nil
 }
 
diff --git a/weed/replication/replicator.go b/weed/replication/replicator.go
index 7353cdc91..a0ef6591c 100644
--- a/weed/replication/replicator.go
+++ b/weed/replication/replicator.go
@@ -18,10 +18,10 @@ type Replicator struct {
 	source *source.FilerSource
 }
 
-func NewReplicator(sourceConfig util.Configuration, dataSink sink.ReplicationSink) *Replicator {
+func NewReplicator(sourceConfig util.Configuration, configPrefix string, dataSink sink.ReplicationSink) *Replicator {
 
 	source := &source.FilerSource{}
-	source.Initialize(sourceConfig)
+	source.Initialize(sourceConfig, configPrefix)
 
 	dataSink.SetSourceFiler(source)
 
diff --git a/weed/replication/sink/azuresink/azure_sink.go b/weed/replication/sink/azuresink/azure_sink.go
index 6381908a1..a0b1a41ab 100644
--- a/weed/replication/sink/azuresink/azure_sink.go
+++ b/weed/replication/sink/azuresink/azure_sink.go
@@ -35,12 +35,12 @@ func (g *AzureSink) GetSinkToDirectory() string {
 	return g.dir
 }
 
-func (g *AzureSink) Initialize(configuration util.Configuration) error {
+func (g *AzureSink) Initialize(configuration util.Configuration, prefix string) error {
 	return g.initialize(
-		configuration.GetString("account_name"),
-		configuration.GetString("account_key"),
-		configuration.GetString("container"),
-		configuration.GetString("directory"),
+		configuration.GetString(prefix+"account_name"),
+		configuration.GetString(prefix+"account_key"),
+		configuration.GetString(prefix+"container"),
+		configuration.GetString(prefix+"directory"),
 	)
 }
 
diff --git a/weed/replication/sink/b2sink/b2_sink.go b/weed/replication/sink/b2sink/b2_sink.go
index 35c2230fa..8c80a64bd 100644
--- a/weed/replication/sink/b2sink/b2_sink.go
+++ b/weed/replication/sink/b2sink/b2_sink.go
@@ -31,12 +31,12 @@ func (g *B2Sink) GetSinkToDirectory() string {
 	return g.dir
 }
 
-func (g *B2Sink) Initialize(configuration util.Configuration) error {
+func (g *B2Sink) Initialize(configuration util.Configuration, prefix string) error {
 	return g.initialize(
-		configuration.GetString("b2_account_id"),
-		configuration.GetString("b2_master_application_key"),
-		configuration.GetString("bucket"),
-		configuration.GetString("directory"),
+		configuration.GetString(prefix+"b2_account_id"),
+		configuration.GetString(prefix+"b2_master_application_key"),
+		configuration.GetString(prefix+"bucket"),
+		configuration.GetString(prefix+"directory"),
 	)
 }
 
diff --git a/weed/replication/sink/filersink/filer_sink.go b/weed/replication/sink/filersink/filer_sink.go
index 4790d1562..de99fbe1c 100644
--- a/weed/replication/sink/filersink/filer_sink.go
+++ b/weed/replication/sink/filersink/filer_sink.go
@@ -3,10 +3,11 @@ package filersink
 import (
 	"context"
 	"fmt"
-	"github.com/chrislusf/seaweedfs/weed/security"
-	"github.com/spf13/viper"
+
 	"google.golang.org/grpc"
 
+	"github.com/chrislusf/seaweedfs/weed/security"
+
 	"github.com/chrislusf/seaweedfs/weed/filer2"
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
@@ -38,13 +39,13 @@ func (fs *FilerSink) GetSinkToDirectory() string {
 	return fs.dir
 }
 
-func (fs *FilerSink) Initialize(configuration util.Configuration) error {
+func (fs *FilerSink) Initialize(configuration util.Configuration, prefix string) error {
 	return fs.initialize(
-		configuration.GetString("grpcAddress"),
-		configuration.GetString("directory"),
-		configuration.GetString("replication"),
-		configuration.GetString("collection"),
-		configuration.GetInt("ttlSec"),
+		configuration.GetString(prefix+"grpcAddress"),
+		configuration.GetString(prefix+"directory"),
+		configuration.GetString(prefix+"replication"),
+		configuration.GetString(prefix+"collection"),
+		configuration.GetInt(prefix+"ttlSec"),
 	)
 }
 
@@ -59,7 +60,7 @@ func (fs *FilerSink) initialize(grpcAddress string, dir string,
 	fs.replication = replication
 	fs.collection = collection
 	fs.ttlSec = int32(ttlSec)
-	fs.grpcDialOption = security.LoadClientTLS(viper.Sub("grpc"), "client")
+	fs.grpcDialOption = security.LoadClientTLS(util.GetViper(), "grpc.client")
 	return nil
 }
 
diff --git a/weed/replication/sink/gcssink/gcs_sink.go b/weed/replication/sink/gcssink/gcs_sink.go
index abd7c49b9..5aa978ab8 100644
--- a/weed/replication/sink/gcssink/gcs_sink.go
+++ b/weed/replication/sink/gcssink/gcs_sink.go
@@ -34,11 +34,11 @@ func (g *GcsSink) GetSinkToDirectory() string {
 	return g.dir
 }
 
-func (g *GcsSink) Initialize(configuration util.Configuration) error {
+func (g *GcsSink) Initialize(configuration util.Configuration, prefix string) error {
 	return g.initialize(
-		configuration.GetString("google_application_credentials"),
-		configuration.GetString("bucket"),
-		configuration.GetString("directory"),
+		configuration.GetString(prefix+"google_application_credentials"),
+		configuration.GetString(prefix+"bucket"),
+		configuration.GetString(prefix+"directory"),
 	)
 }
 
diff --git a/weed/replication/sink/replication_sink.go b/weed/replication/sink/replication_sink.go
index dd54f0005..208bbdf87 100644
--- a/weed/replication/sink/replication_sink.go
+++ b/weed/replication/sink/replication_sink.go
@@ -9,7 +9,7 @@ import (
 
 type ReplicationSink interface {
 	GetName() string
-	Initialize(configuration util.Configuration) error
+	Initialize(configuration util.Configuration, prefix string) error
 	DeleteEntry(ctx context.Context, key string, isDirectory, deleteIncludeChunks bool) error
 	CreateEntry(ctx context.Context, key string, entry *filer_pb.Entry) error
 	UpdateEntry(ctx context.Context, key string, oldEntry *filer_pb.Entry, newParentPath string, newEntry *filer_pb.Entry, deleteIncludeChunks bool) (foundExistingEntry bool, err error)
diff --git a/weed/replication/sink/s3sink/s3_sink.go b/weed/replication/sink/s3sink/s3_sink.go
index 4cff341d0..e4e097c0f 100644
--- a/weed/replication/sink/s3sink/s3_sink.go
+++ b/weed/replication/sink/s3sink/s3_sink.go
@@ -39,16 +39,16 @@ func (s3sink *S3Sink) GetSinkToDirectory() string {
 	return s3sink.dir
 }
 
-func (s3sink *S3Sink) Initialize(configuration util.Configuration) error {
-	glog.V(0).Infof("sink.s3.region: %v", configuration.GetString("region"))
-	glog.V(0).Infof("sink.s3.bucket: %v", configuration.GetString("bucket"))
-	glog.V(0).Infof("sink.s3.directory: %v", configuration.GetString("directory"))
+func (s3sink *S3Sink) Initialize(configuration util.Configuration, prefix string) error {
+	glog.V(0).Infof("sink.s3.region: %v", configuration.GetString(prefix+"region"))
+	glog.V(0).Infof("sink.s3.bucket: %v", configuration.GetString(prefix+"bucket"))
+	glog.V(0).Infof("sink.s3.directory: %v", configuration.GetString(prefix+"directory"))
 	return s3sink.initialize(
-		configuration.GetString("aws_access_key_id"),
-		configuration.GetString("aws_secret_access_key"),
-		configuration.GetString("region"),
-		configuration.GetString("bucket"),
-		configuration.GetString("directory"),
+		configuration.GetString(prefix+"aws_access_key_id"),
+		configuration.GetString(prefix+"aws_secret_access_key"),
+		configuration.GetString(prefix+"region"),
+		configuration.GetString(prefix+"bucket"),
+		configuration.GetString(prefix+"directory"),
 	)
 }
 
diff --git a/weed/replication/source/filer_source.go b/weed/replication/source/filer_source.go
index aef13be75..c3ea44671 100644
--- a/weed/replication/source/filer_source.go
+++ b/weed/replication/source/filer_source.go
@@ -3,13 +3,14 @@ package source
 import (
 	"context"
 	"fmt"
-	"github.com/chrislusf/seaweedfs/weed/security"
-	"github.com/spf13/viper"
-	"google.golang.org/grpc"
 	"io"
 	"net/http"
 	"strings"
 
+	"google.golang.org/grpc"
+
+	"github.com/chrislusf/seaweedfs/weed/security"
+
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
 	"github.com/chrislusf/seaweedfs/weed/util"
@@ -25,17 +26,17 @@ type FilerSource struct {
 	Dir            string
 }
 
-func (fs *FilerSource) Initialize(configuration util.Configuration) error {
+func (fs *FilerSource) Initialize(configuration util.Configuration, prefix string) error {
 	return fs.initialize(
-		configuration.GetString("grpcAddress"),
-		configuration.GetString("directory"),
+		configuration.GetString(prefix+"grpcAddress"),
+		configuration.GetString(prefix+"directory"),
 	)
 }
 
 func (fs *FilerSource) initialize(grpcAddress string, dir string) (err error) {
 	fs.grpcAddress = grpcAddress
 	fs.Dir = dir
-	fs.grpcDialOption = security.LoadClientTLS(viper.Sub("grpc"), "client")
+	fs.grpcDialOption = security.LoadClientTLS(util.GetViper(), "grpc.client")
 	return nil
 }
 
diff --git a/weed/replication/sub/notification_aws_sqs.go b/weed/replication/sub/notification_aws_sqs.go
index bed26c79c..06869e619 100644
--- a/weed/replication/sub/notification_aws_sqs.go
+++ b/weed/replication/sub/notification_aws_sqs.go
@@ -27,14 +27,14 @@ func (k *AwsSqsInput) GetName() string {
 	return "aws_sqs"
 }
 
-func (k *AwsSqsInput) Initialize(configuration util.Configuration) error {
-	glog.V(0).Infof("replication.notification.aws_sqs.region: %v", configuration.GetString("region"))
-	glog.V(0).Infof("replication.notification.aws_sqs.sqs_queue_name: %v", configuration.GetString("sqs_queue_name"))
+func (k *AwsSqsInput) Initialize(configuration util.Configuration, prefix string) error {
+	glog.V(0).Infof("replication.notification.aws_sqs.region: %v", configuration.GetString(prefix+"region"))
+	glog.V(0).Infof("replication.notification.aws_sqs.sqs_queue_name: %v", configuration.GetString(prefix+"sqs_queue_name"))
 	return k.initialize(
-		configuration.GetString("aws_access_key_id"),
-		configuration.GetString("aws_secret_access_key"),
-		configuration.GetString("region"),
-		configuration.GetString("sqs_queue_name"),
+		configuration.GetString(prefix+"aws_access_key_id"),
+		configuration.GetString(prefix+"aws_secret_access_key"),
+		configuration.GetString(prefix+"region"),
+		configuration.GetString(prefix+"sqs_queue_name"),
 	)
 }
 
diff --git a/weed/replication/sub/notification_gocdk_pub_sub.go b/weed/replication/sub/notification_gocdk_pub_sub.go
index eddba9ff8..9726096e5 100644
--- a/weed/replication/sub/notification_gocdk_pub_sub.go
+++ b/weed/replication/sub/notification_gocdk_pub_sub.go
@@ -27,8 +27,8 @@ func (k *GoCDKPubSubInput) GetName() string {
 	return "gocdk_pub_sub"
 }
 
-func (k *GoCDKPubSubInput) Initialize(config util.Configuration) error {
-	subURL := config.GetString("sub_url")
+func (k *GoCDKPubSubInput) Initialize(configuration util.Configuration, prefix string) error {
+	subURL := configuration.GetString(prefix + "sub_url")
 	glog.V(0).Infof("notification.gocdk_pub_sub.sub_url: %v", subURL)
 	sub, err := pubsub.OpenSubscription(context.Background(), subURL)
 	if err != nil {
diff --git a/weed/replication/sub/notification_google_pub_sub.go b/weed/replication/sub/notification_google_pub_sub.go
index ad6b42a2e..a950bb42b 100644
--- a/weed/replication/sub/notification_google_pub_sub.go
+++ b/weed/replication/sub/notification_google_pub_sub.go
@@ -27,13 +27,13 @@ func (k *GooglePubSubInput) GetName() string {
 	return "google_pub_sub"
 }
 
-func (k *GooglePubSubInput) Initialize(configuration util.Configuration) error {
-	glog.V(0).Infof("notification.google_pub_sub.project_id: %v", configuration.GetString("project_id"))
-	glog.V(0).Infof("notification.google_pub_sub.topic: %v", configuration.GetString("topic"))
+func (k *GooglePubSubInput) Initialize(configuration util.Configuration, prefix string) error {
+	glog.V(0).Infof("notification.google_pub_sub.project_id: %v", configuration.GetString(prefix+"project_id"))
+	glog.V(0).Infof("notification.google_pub_sub.topic: %v", configuration.GetString(prefix+"topic"))
 	return k.initialize(
-		configuration.GetString("google_application_credentials"),
-		configuration.GetString("project_id"),
-		configuration.GetString("topic"),
+		configuration.GetString(prefix+"google_application_credentials"),
+		configuration.GetString(prefix+"project_id"),
+		configuration.GetString(prefix+"topic"),
 	)
 }
 
diff --git a/weed/replication/sub/notification_kafka.go b/weed/replication/sub/notification_kafka.go
index 1a86a8307..fa9cfad9b 100644
--- a/weed/replication/sub/notification_kafka.go
+++ b/weed/replication/sub/notification_kafka.go
@@ -28,14 +28,14 @@ func (k *KafkaInput) GetName() string {
 	return "kafka"
 }
 
-func (k *KafkaInput) Initialize(configuration util.Configuration) error {
-	glog.V(0).Infof("replication.notification.kafka.hosts: %v\n", configuration.GetStringSlice("hosts"))
-	glog.V(0).Infof("replication.notification.kafka.topic: %v\n", configuration.GetString("topic"))
+func (k *KafkaInput) Initialize(configuration util.Configuration, prefix string) error {
+	glog.V(0).Infof("replication.notification.kafka.hosts: %v\n", configuration.GetStringSlice(prefix+"hosts"))
+	glog.V(0).Infof("replication.notification.kafka.topic: %v\n", configuration.GetString(prefix+"topic"))
 	return k.initialize(
-		configuration.GetStringSlice("hosts"),
-		configuration.GetString("topic"),
-		configuration.GetString("offsetFile"),
-		configuration.GetInt("offsetSaveIntervalSeconds"),
+		configuration.GetStringSlice(prefix+"hosts"),
+		configuration.GetString(prefix+"topic"),
+		configuration.GetString(prefix+"offsetFile"),
+		configuration.GetInt(prefix+"offsetSaveIntervalSeconds"),
 	)
 }
 
diff --git a/weed/replication/sub/notifications.go b/weed/replication/sub/notifications.go
index 66fbef824..8a2668f98 100644
--- a/weed/replication/sub/notifications.go
+++ b/weed/replication/sub/notifications.go
@@ -9,7 +9,7 @@ type NotificationInput interface {
 	// GetName gets the name to locate the configuration in sync.toml file
 	GetName() string
 	// Initialize initializes the file store
-	Initialize(configuration util.Configuration) error
+	Initialize(configuration util.Configuration, prefix string) error
 	ReceiveMessage() (key string, message *filer_pb.EventNotification, err error)
 }
 
diff --git a/weed/security/tls.go b/weed/security/tls.go
index e81ba4831..f4f525ede 100644
--- a/weed/security/tls.go
+++ b/weed/security/tls.go
@@ -22,7 +22,7 @@ func LoadServerTLS(config *viper.Viper, component string) grpc.ServerOption {
 		glog.Errorf("load cert/key error: %v", err)
 		return nil
 	}
-	caCert, err := ioutil.ReadFile(config.GetString("ca"))
+	caCert, err := ioutil.ReadFile(config.GetString(component + ".ca"))
 	if err != nil {
 		glog.Errorf("read ca cert file error: %v", err)
 		return nil
@@ -49,7 +49,7 @@ func LoadClientTLS(config *viper.Viper, component string) grpc.DialOption {
 		glog.Errorf("load cert/key error: %v", err)
 		return grpc.WithInsecure()
 	}
-	caCert, err := ioutil.ReadFile(config.GetString("ca"))
+	caCert, err := ioutil.ReadFile(config.GetString(component + ".ca"))
 	if err != nil {
 		glog.Errorf("read ca cert file error: %v", err)
 		return grpc.WithInsecure()
diff --git a/weed/server/filer_server.go b/weed/server/filer_server.go
index 3a2eca6d4..72cca1f6f 100644
--- a/weed/server/filer_server.go
+++ b/weed/server/filer_server.go
@@ -14,8 +14,6 @@ import (
 	"github.com/chrislusf/seaweedfs/weed/stats"
 	"github.com/chrislusf/seaweedfs/weed/util"
 
-	"github.com/spf13/viper"
-
 	"github.com/chrislusf/seaweedfs/weed/filer2"
 	_ "github.com/chrislusf/seaweedfs/weed/filer2/cassandra"
 	_ "github.com/chrislusf/seaweedfs/weed/filer2/etcd"
@@ -61,7 +59,7 @@ func NewFilerServer(defaultMux, readonlyMux *http.ServeMux, option *FilerOption)
 
 	fs = &FilerServer{
 		option:         option,
-		grpcDialOption: security.LoadClientTLS(viper.Sub("grpc"), "filer"),
+		grpcDialOption: security.LoadClientTLS(util.GetViper(), "grpc.filer"),
 	}
 
 	if len(option.Masters) == 0 {
@@ -72,7 +70,7 @@ func NewFilerServer(defaultMux, readonlyMux *http.ServeMux, option *FilerOption)
 
 	go fs.filer.KeepConnectedToMaster()
 
-	v := viper.GetViper()
+	v := util.GetViper()
 	if !util.LoadConfiguration("filer", false) {
 		v.Set("leveldb2.enabled", true)
 		v.Set("leveldb2.dir", option.DefaultLevelDbDir)
@@ -86,7 +84,7 @@ func NewFilerServer(defaultMux, readonlyMux *http.ServeMux, option *FilerOption)
 	fs.option.recursiveDelete = v.GetBool("filer.options.recursive_delete")
 	fs.filer.LoadConfiguration(v)
 
-	notification.LoadConfiguration(v.Sub("notification"))
+	notification.LoadConfiguration(v, "notification.")
 
 	handleStaticResources(defaultMux)
 	if !option.DisableHttp {
diff --git a/weed/server/master_server.go b/weed/server/master_server.go
index 33a5129da..b3cc310e6 100644
--- a/weed/server/master_server.go
+++ b/weed/server/master_server.go
@@ -14,6 +14,9 @@ import (
 	"time"
 
 	"github.com/chrislusf/raft"
+	"github.com/gorilla/mux"
+	"google.golang.org/grpc"
+
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/pb/master_pb"
 	"github.com/chrislusf/seaweedfs/weed/security"
@@ -22,9 +25,6 @@ import (
 	"github.com/chrislusf/seaweedfs/weed/topology"
 	"github.com/chrislusf/seaweedfs/weed/util"
 	"github.com/chrislusf/seaweedfs/weed/wdclient"
-	"github.com/gorilla/mux"
-	"github.com/spf13/viper"
-	"google.golang.org/grpc"
 )
 
 const (
@@ -69,7 +69,7 @@ type MasterServer struct {
 
 func NewMasterServer(r *mux.Router, option *MasterOption, peers []string) *MasterServer {
 
-	v := viper.GetViper()
+	v := util.GetViper()
 	signingKey := v.GetString("jwt.signing.key")
 	v.SetDefault("jwt.signing.expires_after_seconds", 10)
 	expiresAfterSec := v.GetInt("jwt.signing.expires_after_seconds")
@@ -83,7 +83,7 @@ func NewMasterServer(r *mux.Router, option *MasterOption, peers []string) *Maste
 		preallocateSize = int64(option.VolumeSizeLimitMB) * (1 << 20)
 	}
 
-	grpcDialOption := security.LoadClientTLS(v.Sub("grpc"), "master")
+	grpcDialOption := security.LoadClientTLS(v, "grpc.master")
 	ms := &MasterServer{
 		option:          option,
 		preallocateSize: preallocateSize,
@@ -183,7 +183,7 @@ func (ms *MasterServer) proxyToLeader(f func(w http.ResponseWriter, r *http.Requ
 func (ms *MasterServer) startAdminScripts() {
 	var err error
 
-	v := viper.GetViper()
+	v := util.GetViper()
 	adminScripts := v.GetString("master.maintenance.scripts")
 	glog.V(0).Infof("adminScripts:\n%v", adminScripts)
 	if adminScripts == "" {
@@ -201,7 +201,7 @@ func (ms *MasterServer) startAdminScripts() {
 	masterAddress := "localhost:" + strconv.Itoa(ms.option.Port)
 
 	var shellOptions shell.ShellOptions
-	shellOptions.GrpcDialOption = security.LoadClientTLS(viper.Sub("grpc"), "master")
+	shellOptions.GrpcDialOption = security.LoadClientTLS(v, "grpc.master")
 	shellOptions.Masters = &masterAddress
 
 	shellOptions.FilerHost, shellOptions.FilerPort, shellOptions.Directory, err = util.ParseFilerUrl(filerURL)
@@ -250,7 +250,7 @@ func (ms *MasterServer) startAdminScripts() {
 
 func (ms *MasterServer) createSequencer(option *MasterOption) sequence.Sequencer {
 	var seq sequence.Sequencer
-	v := viper.GetViper()
+	v := util.GetViper()
 	seqType := strings.ToLower(v.GetString(SequencerType))
 	glog.V(1).Infof("[%s] : [%s]", SequencerType, seqType)
 	switch strings.ToLower(seqType) {
diff --git a/weed/server/volume_grpc_client_to_master.go b/weed/server/volume_grpc_client_to_master.go
index 6038752d2..dc47c2884 100644
--- a/weed/server/volume_grpc_client_to_master.go
+++ b/weed/server/volume_grpc_client_to_master.go
@@ -5,16 +5,17 @@ import (
 	"net"
 	"time"
 
+	"google.golang.org/grpc"
+
 	"github.com/chrislusf/seaweedfs/weed/security"
 	"github.com/chrislusf/seaweedfs/weed/storage/backend"
 	"github.com/chrislusf/seaweedfs/weed/storage/erasure_coding"
-	"github.com/spf13/viper"
-	"google.golang.org/grpc"
+
+	"golang.org/x/net/context"
 
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/pb/master_pb"
 	"github.com/chrislusf/seaweedfs/weed/util"
-	"golang.org/x/net/context"
 )
 
 func (vs *VolumeServer) GetMaster() string {
@@ -26,7 +27,7 @@ func (vs *VolumeServer) heartbeat() {
 	vs.store.SetDataCenter(vs.dataCenter)
 	vs.store.SetRack(vs.rack)
 
-	grpcDialOption := security.LoadClientTLS(viper.Sub("grpc"), "volume")
+	grpcDialOption := security.LoadClientTLS(util.GetViper(), "grpc.volume")
 
 	var err error
 	var newLeader string
diff --git a/weed/server/volume_server.go b/weed/server/volume_server.go
index a406b36cc..0fdcf662a 100644
--- a/weed/server/volume_server.go
+++ b/weed/server/volume_server.go
@@ -7,8 +7,7 @@ import (
 	"google.golang.org/grpc"
 
 	"github.com/chrislusf/seaweedfs/weed/stats"
-
-	"github.com/spf13/viper"
+	"github.com/chrislusf/seaweedfs/weed/util"
 
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/security"
@@ -47,7 +46,7 @@ func NewVolumeServer(adminMux, publicMux *http.ServeMux, ip string,
 	fileSizeLimitMB int,
 ) *VolumeServer {
 
-	v := viper.GetViper()
+	v := util.GetViper()
 	signingKey := v.GetString("jwt.signing.key")
 	v.SetDefault("jwt.signing.expires_after_seconds", 10)
 	expiresAfterSec := v.GetInt("jwt.signing.expires_after_seconds")
@@ -64,7 +63,7 @@ func NewVolumeServer(adminMux, publicMux *http.ServeMux, ip string,
 		needleMapKind:           needleMapKind,
 		FixJpgOrientation:       fixJpgOrientation,
 		ReadRedirect:            readRedirect,
-		grpcDialOption:          security.LoadClientTLS(viper.Sub("grpc"), "volume"),
+		grpcDialOption:          security.LoadClientTLS(util.GetViper(), "grpc.volume"),
 		compactionBytePerSecond: int64(compactionMBPerSecond) * 1024 * 1024,
 		fileSizeLimitBytes:      int64(fileSizeLimitMB) * 1024 * 1024,
 	}
diff --git a/weed/server/webdav_server.go b/weed/server/webdav_server.go
index bdb6b61a9..d75869f30 100644
--- a/weed/server/webdav_server.go
+++ b/weed/server/webdav_server.go
@@ -17,8 +17,6 @@ import (
 	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
 	"github.com/chrislusf/seaweedfs/weed/util"
 
-	"github.com/spf13/viper"
-
 	"github.com/chrislusf/seaweedfs/weed/filer2"
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/security"
@@ -49,7 +47,7 @@ func NewWebDavServer(option *WebDavOption) (ws *WebDavServer, err error) {
 
 	ws = &WebDavServer{
 		option:         option,
-		grpcDialOption: security.LoadClientTLS(viper.Sub("grpc"), "filer"),
+		grpcDialOption: security.LoadClientTLS(util.GetViper(), "grpc.filer"),
 		Handler: &webdav.Handler{
 			FileSystem: fs,
 			LockSystem: webdav.NewMemLS(),
diff --git a/weed/shell/command_fs_meta_notify.go b/weed/shell/command_fs_meta_notify.go
index a898df7a0..e2b2d22cc 100644
--- a/weed/shell/command_fs_meta_notify.go
+++ b/weed/shell/command_fs_meta_notify.go
@@ -5,8 +5,6 @@ import (
 	"fmt"
 	"io"
 
-	"github.com/spf13/viper"
-
 	"github.com/chrislusf/seaweedfs/weed/filer2"
 	"github.com/chrislusf/seaweedfs/weed/notification"
 	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
@@ -42,8 +40,8 @@ func (c *commandFsMetaNotify) Do(args []string, commandEnv *CommandEnv, writer i
 	}
 
 	util.LoadConfiguration("notification", true)
-	v := viper.GetViper()
-	notification.LoadConfiguration(v.Sub("notification"))
+	v := util.GetViper()
+	notification.LoadConfiguration(v, "notification.")
 
 	ctx := context.Background()
 
diff --git a/weed/storage/backend/backend.go b/weed/storage/backend/backend.go
index 6ea850543..6941ca5a1 100644
--- a/weed/storage/backend/backend.go
+++ b/weed/storage/backend/backend.go
@@ -35,7 +35,7 @@ type StringProperties interface {
 type StorageType string
 type BackendStorageFactory interface {
 	StorageType() StorageType
-	BuildStorage(configuration StringProperties, id string) (BackendStorage, error)
+	BuildStorage(configuration StringProperties, configPrefix string, id string) (BackendStorage, error)
 }
 
 var (
@@ -48,19 +48,17 @@ func LoadConfiguration(config *viper.Viper) {
 
 	StorageBackendPrefix := "storage.backend"
 
-	backendSub := config.Sub(StorageBackendPrefix)
-
 	for backendTypeName := range config.GetStringMap(StorageBackendPrefix) {
 		backendStorageFactory, found := BackendStorageFactories[StorageType(backendTypeName)]
 		if !found {
 			glog.Fatalf("backend storage type %s not found", backendTypeName)
 		}
-		backendTypeSub := backendSub.Sub(backendTypeName)
-		for backendStorageId := range backendSub.GetStringMap(backendTypeName) {
-			if !backendTypeSub.GetBool(backendStorageId + ".enabled") {
+		for backendStorageId := range config.GetStringMap(StorageBackendPrefix + "." + backendTypeName) {
+			if !config.GetBool(StorageBackendPrefix + "." + backendTypeName + "." + backendStorageId + ".enabled") {
 				continue
 			}
-			backendStorage, buildErr := backendStorageFactory.BuildStorage(backendTypeSub.Sub(backendStorageId), backendStorageId)
+			backendStorage, buildErr := backendStorageFactory.BuildStorage(config,
+				StorageBackendPrefix+"."+backendTypeName+"."+backendStorageId+".", backendStorageId)
 			if buildErr != nil {
 				glog.Fatalf("fail to create backend storage %s.%s", backendTypeName, backendStorageId)
 			}
@@ -82,7 +80,7 @@ func LoadFromPbStorageBackends(storageBackends []*master_pb.StorageBackend) {
 			glog.Warningf("storage type %s not found", storageBackend.Type)
 			continue
 		}
-		backendStorage, buildErr := backendStorageFactory.BuildStorage(newProperties(storageBackend.Properties), storageBackend.Id)
+		backendStorage, buildErr := backendStorageFactory.BuildStorage(newProperties(storageBackend.Properties), "", storageBackend.Id)
 		if buildErr != nil {
 			glog.Fatalf("fail to create backend storage %s.%s", storageBackend.Type, storageBackend.Id)
 		}
diff --git a/weed/storage/backend/s3_backend/s3_backend.go b/weed/storage/backend/s3_backend/s3_backend.go
index 9f03cfa81..8d71861c2 100644
--- a/weed/storage/backend/s3_backend/s3_backend.go
+++ b/weed/storage/backend/s3_backend/s3_backend.go
@@ -26,8 +26,8 @@ type S3BackendFactory struct {
 func (factory *S3BackendFactory) StorageType() backend.StorageType {
 	return backend.StorageType("s3")
 }
-func (factory *S3BackendFactory) BuildStorage(configuration backend.StringProperties, id string) (backend.BackendStorage, error) {
-	return newS3BackendStorage(configuration, id)
+func (factory *S3BackendFactory) BuildStorage(configuration backend.StringProperties, configPrefix string, id string) (backend.BackendStorage, error) {
+	return newS3BackendStorage(configuration, configPrefix, id)
 }
 
 type S3BackendStorage struct {
@@ -39,13 +39,13 @@ type S3BackendStorage struct {
 	conn                  s3iface.S3API
 }
 
-func newS3BackendStorage(configuration backend.StringProperties, id string) (s *S3BackendStorage, err error) {
+func newS3BackendStorage(configuration backend.StringProperties, configPrefix string, id string) (s *S3BackendStorage, err error) {
 	s = &S3BackendStorage{}
 	s.id = id
-	s.aws_access_key_id = configuration.GetString("aws_access_key_id")
-	s.aws_secret_access_key = configuration.GetString("aws_secret_access_key")
-	s.region = configuration.GetString("region")
-	s.bucket = configuration.GetString("bucket")
+	s.aws_access_key_id = configuration.GetString(configPrefix + "aws_access_key_id")
+	s.aws_secret_access_key = configuration.GetString(configPrefix + "aws_secret_access_key")
+	s.region = configuration.GetString(configPrefix + "region")
+	s.bucket = configuration.GetString(configPrefix + "bucket")
 	s.conn, err = createSession(s.aws_access_key_id, s.aws_secret_access_key, s.region)
 
 	glog.V(0).Infof("created backend storage s3.%s for region %s bucket %s", s.id, s.region, s.bucket)
diff --git a/weed/storage/volume_vacuum.go b/weed/storage/volume_vacuum.go
index 0ca9016c8..523b37e34 100644
--- a/weed/storage/volume_vacuum.go
+++ b/weed/storage/volume_vacuum.go
@@ -356,7 +356,7 @@ func (v *Volume) copyDataAndGenerateIndexFile(dstName, idxName string, prealloca
 func copyDataBasedOnIndexFile(srcDatName, srcIdxName, dstDatName, datIdxName string, sb super_block.SuperBlock, version needle.Version, preallocate int64) (err error) {
 	var (
 		srcDatBackend, dstDatBackend backend.BackendStorageFile
-		dataFile *os.File
+		dataFile                     *os.File
 	)
 	if dstDatBackend, err = createVolumeFile(dstDatName, preallocate, 0); err != nil {
 		return
diff --git a/weed/util/config.go b/weed/util/config.go
index 7b86b749e..dfbfdbd82 100644
--- a/weed/util/config.go
+++ b/weed/util/config.go
@@ -1,8 +1,11 @@
 package util
 
 import (
-	"github.com/chrislusf/seaweedfs/weed/glog"
+	"strings"
+
 	"github.com/spf13/viper"
+
+	"github.com/chrislusf/seaweedfs/weed/glog"
 )
 
 type Configuration interface {
@@ -37,3 +40,11 @@ func LoadConfiguration(configFileName string, required bool) (loaded bool) {
 
 	return true
 }
+
+func GetViper() *viper.Viper {
+	v := viper.GetViper()
+	v.AutomaticEnv()
+	v.SetEnvPrefix("weed")
+	v.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))
+	return v
+}
diff --git a/weed/util/config_test.go b/weed/util/config_test.go
new file mode 100644
index 000000000..659814a4a
--- /dev/null
+++ b/weed/util/config_test.go
@@ -0,0 +1,24 @@
+package util
+
+import (
+	"os"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestAllKeysWithEnv(t *testing.T) {
+
+	v := GetViper()
+	v.BindEnv("id")
+	v.BindEnv("foo", "foo")
+
+	// bind and define environment variables (including a nested one)
+	os.Setenv("WEED_ID", "13")
+	os.Setenv("WEED_FOO_BAR", "baz")
+
+	sub := v.Sub("foo")
+
+	assert.Equal(t, "13", v.GetString("id"))
+	assert.Equal(t, "baz", sub.GetString("bar"))
+}