diff --git a/weed/filer2/filechunks.go b/weed/filer2/filechunks.go
index 0ac7bb43b..e47cb762f 100644
--- a/weed/filer2/filechunks.go
+++ b/weed/filer2/filechunks.go
@@ -3,6 +3,8 @@ package filer2
 import (
 	"math"
 	"sort"
+	"hash/fnv"
+	"fmt"
 
 	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
 )
@@ -17,6 +19,18 @@ func TotalSize(chunks []*filer_pb.FileChunk) (size uint64) {
 	return
 }
 
+func ETag(chunks []*filer_pb.FileChunk) (etag string) {
+	if len(chunks) == 1 {
+		return chunks[0].ETag
+	}
+
+	h := fnv.New32a()
+	for _, c := range chunks {
+		h.Write([]byte(c.ETag))
+	}
+	return fmt.Sprintf("%x", h.Sum32())
+}
+
 func CompactFileChunks(chunks []*filer_pb.FileChunk) (compacted, garbage []*filer_pb.FileChunk) {
 
 	visibles := nonOverlappingVisibleIntervals(chunks)
diff --git a/weed/pb/filer.proto b/weed/pb/filer.proto
index fc06c3e84..e2b175c11 100644
--- a/weed/pb/filer.proto
+++ b/weed/pb/filer.proto
@@ -76,6 +76,7 @@ message FileChunk {
     int64 offset = 2;
     uint64 size = 3;
     int64 mtime = 4;
+    string e_tag = 5;
 }
 
 message FuseAttributes {
diff --git a/weed/pb/filer_pb/filer.pb.go b/weed/pb/filer_pb/filer.pb.go
index 27e5886c3..7ee8a7dd2 100644
--- a/weed/pb/filer_pb/filer.pb.go
+++ b/weed/pb/filer_pb/filer.pb.go
@@ -239,6 +239,7 @@ type FileChunk struct {
 	Offset int64  `protobuf:"varint,2,opt,name=offset" json:"offset,omitempty"`
 	Size   uint64 `protobuf:"varint,3,opt,name=size" json:"size,omitempty"`
 	Mtime  int64  `protobuf:"varint,4,opt,name=mtime" json:"mtime,omitempty"`
+	ETag   string `protobuf:"bytes,5,opt,name=e_tag,json=eTag" json:"e_tag,omitempty"`
 }
 
 func (m *FileChunk) Reset()                    { *m = FileChunk{} }
@@ -274,6 +275,13 @@ func (m *FileChunk) GetMtime() int64 {
 	return 0
 }
 
+func (m *FileChunk) GetETag() string {
+	if m != nil {
+		return m.ETag
+	}
+	return ""
+}
+
 type FuseAttributes struct {
 	FileSize    uint64 `protobuf:"varint,1,opt,name=file_size,json=fileSize" json:"file_size,omitempty"`
 	Mtime       int64  `protobuf:"varint,2,opt,name=mtime" json:"mtime,omitempty"`
@@ -1130,81 +1138,82 @@ var _SeaweedFiler_serviceDesc = grpc.ServiceDesc{
 func init() { proto.RegisterFile("filer.proto", fileDescriptor0) }
 
 var fileDescriptor0 = []byte{
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+	0x98, 0x4f, 0x0d, 0x27, 0x86, 0xd5, 0x83, 0x0b, 0x8c, 0xd8, 0x51, 0xcc, 0xe8, 0x19, 0xf5, 0x3d,
+	0x46, 0xe3, 0x88, 0x6c, 0x81, 0x15, 0x87, 0xc1, 0x48, 0xb6, 0x98, 0x59, 0xdf, 0x62, 0x9d, 0x38,
+	0x54, 0xe1, 0xb6, 0xc0, 0x8a, 0xf0, 0x52, 0x59, 0x37, 0x16, 0x58, 0x47, 0x78, 0x29, 0x56, 0xce,
+	0xaf, 0x60, 0x15, 0x75, 0x23, 0xf7, 0x60, 0x99, 0x1b, 0x8e, 0x68, 0xa0, 0xd0, 0xb6, 0xf9, 0xf6,
+	0x75, 0xc0, 0x9b, 0x30, 0x3e, 0x3b, 0x4b, 0x91, 0x89, 0xf0, 0x0d, 0x57, 0xed, 0xf8, 0x47, 0x4c,
+	0xe9, 0x2f, 0xb2, 0xef, 0x9a, 0xae, 0x58, 0xf3, 0xe4, 0x26, 0x8c, 0x4e, 0x50, 0xd4, 0xbb, 0xe1,
+	0xca, 0x0d, 0xe9, 0x43, 0x0b, 0x47, 0xcc, 0x1b, 0x8b, 0x86, 0xb2, 0xdc, 0x26, 0xbe, 0xf3, 0xc6,
+	0xce, 0x6f, 0x26, 0xdc, 0x2a, 0x7f, 0x04, 0x72, 0x1f, 0x2c, 0x01, 0x41, 0xb8, 0x35, 0x84, 0x5b,
+	0x31, 0xd8, 0xc7, 0x25, 0xd7, 0xa6, 0xee, 0x3a, 0x3f, 0x32, 0x89, 0x03, 0x89, 0x64, 0x45, 0x1e,
+	0x79, 0x13, 0x07, 0xc8, 0x8b, 0x9f, 0xd1, 0x40, 0x60, 0x59, 0x71, 0xf9, 0x92, 0x4b, 0xc6, 0x34,
+	0x50, 0x8d, 0xcd, 0x97, 0x3c, 0x3b, 0x3f, 0x11, 0x7e, 0xdb, 0x32, 0x3b, 0xb9, 0xe3, 0xd9, 0x4d,
+	0xb8, 0x74, 0x59, 0x42, 0xe6, 0x6b, 0x32, 0x84, 0x6e, 0x82, 0xd3, 0x50, 0x7d, 0x1a, 0xbb, 0x23,
+	0x54, 0xba, 0x88, 0x3c, 0x00, 0xf0, 0xe3, 0x30, 0x44, 0x5f, 0x18, 0x58, 0xc2, 0x40, 0x93, 0xf0,
+	0x22, 0x33, 0x16, 0x8e, 0x52, 0xf4, 0x6d, 0x18, 0x1a, 0x9b, 0x2d, 0xb7, 0xcd, 0x58, 0x78, 0x8c,
+	0xbe, 0x33, 0x86, 0xff, 0xbf, 0x42, 0x31, 0x5c, 0x57, 0x5a, 0x57, 0x2a, 0x92, 0xa8, 0x1b, 0x97,
+	0x0d, 0x80, 0xa9, 0x97, 0x60, 0xc4, 0xf8, 0xc8, 0x28, 0x7a, 0xb0, 0xa4, 0x64, 0x9f, 0x26, 0xfa,
+	0xd7, 0x6c, 0xe8, 0x5f, 0xd3, 0xf9, 0xdd, 0x84, 0x41, 0x5d, 0x24, 0x35, 0xce, 0xe5, 0xa9, 0x31,
+	0x6e, 0x30, 0x35, 0xb3, 0xe1, 0x34, 0x3f, 0x3c, 0x9c, 0x47, 0xda, 0x88, 0xc9, 0x59, 0xde, 0x9d,
+	0x99, 0x2f, 0x86, 0xf7, 0x69, 0xe6, 0x6e, 0x07, 0xee, 0xbc, 0x42, 0x26, 0x40, 0xc6, 0x11, 0xc3,
+	0x88, 0xe5, 0x75, 0x5f, 0x34, 0x12, 0xce, 0x2e, 0xdc, 0x9d, 0x3f, 0xa1, 0xea, 0x67, 0xc3, 0xb2,
+	0x2f, 0x45, 0xe2, 0x48, 0xcf, 0xcd, 0xb7, 0xce, 0x0f, 0x40, 0xf6, 0x12, 0xf4, 0x18, 0xde, 0xe0,
+	0x3e, 0x2a, 0xee, 0x16, 0xf3, 0xda, 0xbb, 0xe5, 0x0e, 0xf4, 0x4b, 0xae, 0x25, 0x16, 0x1e, 0xf1,
+	0x64, 0x1a, 0x7c, 0xaa, 0x88, 0x25, 0xd7, 0x2a, 0xe2, 0xdf, 0x06, 0x90, 0x7d, 0x0c, 0xf1, 0x46,
+	0x21, 0x6b, 0x2e, 0xdd, 0xca, 0x65, 0xd0, 0xa8, 0x5e, 0x06, 0x8f, 0xe0, 0x16, 0x37, 0x11, 0xd1,
+	0x46, 0x81, 0xc7, 0x3c, 0x75, 0xa3, 0xf5, 0x68, 0x2a, 0x21, 0xec, 0x7b, 0xcc, 0x53, 0x8e, 0x12,
+	0xf4, 0xb3, 0x84, 0x5f, 0x72, 0x62, 0xf2, 0x85, 0x23, 0x37, 0x17, 0xf1, 0x5c, 0x4a, 0x98, 0x55,
+	0x2e, 0x7f, 0x19, 0xd0, 0x7f, 0x91, 0xa6, 0x74, 0x1c, 0x7d, 0x1f, 0x87, 0xd9, 0x04, 0xf3, 0x64,
+	0xd6, 0xa0, 0xe5, 0xc7, 0x99, 0xfa, 0xbe, 0x2d, 0x57, 0x6e, 0xe6, 0x06, 0xdf, 0xac, 0x0c, 0xfe,
+	0x1c, 0x75, 0x34, 0xaa, 0xd4, 0xa1, 0x51, 0x43, 0x53, 0xa7, 0x06, 0xf2, 0x19, 0x74, 0x79, 0x7a,
+	0x23, 0x1f, 0x23, 0x86, 0x89, 0xe2, 0x50, 0xe0, 0xa2, 0x3d, 0x21, 0x71, 0x2e, 0x60, 0xad, 0x0c,
+	0x54, 0xf5, 0xe2, 0x42, 0x46, 0xe7, 0xbc, 0x98, 0x84, 0x0a, 0x25, 0x5f, 0x0a, 0x36, 0xc9, 0x4e,
+	0x43, 0xea, 0x8f, 0xb8, 0xa2, 0xa1, 0xd8, 0x44, 0x48, 0x4e, 0x92, 0x70, 0x96, 0x73, 0x53, 0xcb,
+	0xd9, 0xf9, 0x1a, 0xfa, 0xf2, 0x65, 0x54, 0x2e, 0xd0, 0x06, 0xc0, 0x85, 0x10, 0x8c, 0x68, 0x20,
+	0x1f, 0x05, 0x96, 0x6b, 0x49, 0xc9, 0xeb, 0x20, 0x75, 0xbe, 0x05, 0xeb, 0x30, 0x96, 0x39, 0xa7,
+	0x64, 0x07, 0xac, 0x30, 0xdf, 0xa8, 0xf7, 0x03, 0x99, 0xb5, 0x5c, 0x6e, 0xe7, 0xce, 0x8c, 0x9c,
+	0xe7, 0xd0, 0xc9, 0xc5, 0x79, 0x1e, 0xc6, 0xa2, 0x3c, 0xcc, 0xb9, 0x3c, 0x9c, 0x7f, 0x0d, 0x58,
+	0x2b, 0x43, 0x56, 0xa5, 0x3a, 0x81, 0x95, 0x22, 0xc4, 0x68, 0xe2, 0x4d, 0x15, 0x96, 0x1d, 0x1d,
+	0x4b, 0xf5, 0x58, 0x01, 0x30, 0x7d, 0xe3, 0x4d, 0x65, 0xf7, 0xf4, 0x42, 0x4d, 0x34, 0x78, 0x07,
+	0xab, 0x15, 0x93, 0x1a, 0x6a, 0x7a, 0xa2, 0x53, 0x53, 0x89, 0x39, 0x8b, 0xd3, 0x3a, 0x5f, 0x3d,
+	0x83, 0x7b, 0xb2, 0x61, 0xf7, 0x8a, 0xfe, 0xca, 0x6b, 0x5f, 0x6e, 0x43, 0x63, 0xbe, 0x0d, 0x9d,
+	0x01, 0xd8, 0xd5, 0xa3, 0x32, 0x99, 0xdd, 0x3f, 0xda, 0xd0, 0x3b, 0x46, 0xef, 0x12, 0x31, 0xe0,
+	0xcc, 0x96, 0x90, 0x71, 0x5e, 0xac, 0xf2, 0xcb, 0x97, 0x3c, 0x9e, 0xaf, 0x4a, 0xed, 0x53, 0x7b,
+	0xf0, 0xc5, 0x87, 0xcc, 0xd4, 0xa0, 0x2d, 0x91, 0x43, 0xe8, 0x6a, 0x4f, 0x4b, 0xb2, 0xae, 0x1d,
+	0xac, 0xbc, 0x98, 0x07, 0x1b, 0x0b, 0xb4, 0x85, 0x37, 0x0f, 0x48, 0xf5, 0x06, 0x21, 0x9f, 0x5f,
+	0x7f, 0xbf, 0x48, 0xdf, 0x8f, 0x3e, 0xe6, 0x12, 0x92, 0x80, 0x35, 0xc2, 0xd5, 0x01, 0x57, 0x29,
+	0x5e, 0x07, 0x5c, 0xc7, 0xd2, 0xc2, 0x9b, 0x46, 0xa6, 0xba, 0xb7, 0x2a, 0x7d, 0xeb, 0xde, 0xea,
+	0x18, 0x58, 0x78, 0xd3, 0xe8, 0x4c, 0xf7, 0x56, 0x65, 0x66, 0xdd, 0x5b, 0x1d, 0x07, 0x2e, 0x91,
+	0xb7, 0xd0, 0xd3, 0xb9, 0x85, 0x68, 0x07, 0x6a, 0xc8, 0x71, 0xf0, 0x60, 0x91, 0x5a, 0x77, 0xa8,
+	0x8f, 0x92, 0xee, 0xb0, 0x86, 0x4c, 0x74, 0x87, 0x75, 0x13, 0xe8, 0x2c, 0x91, 0x1f, 0xe1, 0xf6,
+	0x7c, 0x4b, 0x93, 0x87, 0xf3, 0x69, 0x55, 0x26, 0x65, 0xe0, 0x5c, 0x67, 0x92, 0x3b, 0x3f, 0x6d,
+	0x8b, 0xdf, 0xcb, 0xaf, 0xfe, 0x0b, 0x00, 0x00, 0xff, 0xff, 0xbf, 0xe3, 0x2a, 0x44, 0x6d, 0x0e,
 	0x00, 0x00,
 }
diff --git a/weed/s3api/filer_multipart.go b/weed/s3api/filer_multipart.go
index cd5b2e118..d9cafae26 100644
--- a/weed/s3api/filer_multipart.go
+++ b/weed/s3api/filer_multipart.go
@@ -1,11 +1,18 @@
 package s3api
 
 import (
+	"fmt"
+	"time"
+	"strings"
+	"strconv"
+	"path/filepath"
+
 	"github.com/aws/aws-sdk-go/service/s3"
 	"github.com/aws/aws-sdk-go/aws"
 	"github.com/satori/go.uuid"
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
+	"github.com/chrislusf/seaweedfs/weed/filer2"
 )
 
 func (s3a *S3ApiServer) createMultipartUpload(input *s3.CreateMultipartUploadInput) (output *s3.CreateMultipartUploadOutput, code ErrorCode) {
@@ -32,19 +39,76 @@ func (s3a *S3ApiServer) createMultipartUpload(input *s3.CreateMultipartUploadInp
 }
 
 func (s3a *S3ApiServer) completeMultipartUpload(input *s3.CompleteMultipartUploadInput) (output *s3.CompleteMultipartUploadOutput, code ErrorCode) {
+
+	uploadDirectory := s3a.genUploadsFolder(*input.Bucket) + "/" + *input.UploadId
+
+	entries, err := s3a.list(uploadDirectory, "", "", false, 0)
+	if err != nil {
+		glog.Errorf("completeMultipartUpload %s *s error: %v", *input.Bucket, *input.UploadId, err)
+		return nil, ErrNoSuchUpload
+	}
+
+	var finalParts []*filer_pb.FileChunk
+	var offset int64
+
+	for _, entry := range entries {
+		if strings.HasSuffix(entry.Name, ".part") && !entry.IsDirectory {
+			for _, chunk := range entry.Chunks {
+				finalParts = append(finalParts, &filer_pb.FileChunk{
+					FileId: chunk.FileId,
+					Offset: offset,
+					Size:   chunk.Size,
+					Mtime:  chunk.Mtime,
+					ETag:   chunk.ETag,
+				})
+				offset += int64(chunk.Size)
+			}
+		}
+	}
+
+	entryName := filepath.Base(*input.Key)
+	dirName := filepath.Dir(*input.Key)
+	if dirName == "." {
+		dirName = ""
+	}
+	dirName = fmt.Sprintf("%s/%s/%s", s3a.option.BucketsPath, *input.Bucket, dirName)
+
+	err = s3a.mkFile(dirName, entryName, finalParts)
+
+	if err != nil {
+		glog.Errorf("completeMultipartUpload %s/%s error: %v", dirName, entryName, err)
+		return nil, ErrInternalError
+	}
+
+	output = &s3.CompleteMultipartUploadOutput{
+		Bucket: input.Bucket,
+		ETag:   aws.String("\"" + filer2.ETag(finalParts) + "\""),
+		Key:    input.Key,
+	}
+
 	return
 }
 
 func (s3a *S3ApiServer) abortMultipartUpload(input *s3.AbortMultipartUploadInput) (output *s3.AbortMultipartUploadOutput, code ErrorCode) {
-	return
-}
 
-func (s3a *S3ApiServer) listMultipartUploads(input *s3.ListMultipartUploadsInput) (output *s3.ListMultipartUploadsOutput, code ErrorCode) {
-	entries, err := s3a.list(s3a.genUploadsFolder(*input.Bucket))
+	exists, err := s3a.exists(s3a.genUploadsFolder(*input.Bucket), *input.UploadId, true)
 	if err != nil {
-		glog.Errorf("listMultipartUploads %s error: %v", *input.Bucket, err)
+		glog.V(1).Infof("bucket %s abort upload %s: %v", *input.Bucket, *input.UploadId, err)
 		return nil, ErrNoSuchUpload
 	}
+	if exists {
+		err = s3a.rm(s3a.genUploadsFolder(*input.Bucket), *input.UploadId, true, true, true)
+	}
+	if err != nil {
+		glog.V(1).Infof("bucket %s remove upload %s: %v", *input.Bucket, *input.UploadId, err)
+		return nil, ErrInternalError
+	}
+
+	return &s3.AbortMultipartUploadOutput{}, ErrNone
+}
+
+func (s3a *S3ApiServer) listMultipartUploads(input *s3.ListMultipartUploadsInput) (output *s3.ListMultipartUploadsOutput, code ErrorCode) {
+
 	output = &s3.ListMultipartUploadsOutput{
 		Bucket:       input.Bucket,
 		Delimiter:    input.Delimiter,
@@ -53,6 +117,13 @@ func (s3a *S3ApiServer) listMultipartUploads(input *s3.ListMultipartUploadsInput
 		MaxUploads:   input.MaxUploads,
 		Prefix:       input.Prefix,
 	}
+
+	entries, err := s3a.list(s3a.genUploadsFolder(*input.Bucket), *input.Prefix, *input.KeyMarker, true, int(*input.MaxUploads))
+	if err != nil {
+		glog.Errorf("listMultipartUploads %s error: %v", *input.Bucket, err)
+		return
+	}
+
 	for _, entry := range entries {
 		if entry.Extended != nil {
 			key := entry.Extended["key"]
@@ -66,5 +137,37 @@ func (s3a *S3ApiServer) listMultipartUploads(input *s3.ListMultipartUploadsInput
 }
 
 func (s3a *S3ApiServer) listObjectParts(input *s3.ListPartsInput) (output *s3.ListPartsOutput, code ErrorCode) {
+	output = &s3.ListPartsOutput{
+		Bucket:           input.Bucket,
+		Key:              input.Key,
+		UploadId:         input.UploadId,
+		MaxParts:         input.MaxParts,         // the maximum number of parts to return.
+		PartNumberMarker: input.PartNumberMarker, // the part number starts after this, exclusive
+	}
+
+	entries, err := s3a.list(s3a.genUploadsFolder(*input.Bucket)+"/"+*input.UploadId,
+		"", fmt.Sprintf("%04d.part", *input.PartNumberMarker), false, int(*input.MaxParts))
+	if err != nil {
+		glog.Errorf("listObjectParts %s *s error: %v", *input.Bucket, *input.UploadId, err)
+		return nil, ErrNoSuchUpload
+	}
+
+	for _, entry := range entries {
+		if strings.HasSuffix(entry.Name, ".part") && !entry.IsDirectory {
+			partNumberString := entry.Name[:len(entry.Name)-len(".part")]
+			partNumber, err := strconv.Atoi(partNumberString)
+			if err != nil {
+				glog.Errorf("listObjectParts %s *s parse %s: %v", *input.Bucket, *input.UploadId, entry.Name, err)
+				continue
+			}
+			output.Parts = append(output.Parts, &s3.Part{
+				PartNumber:   aws.Int64(int64(partNumber)),
+				LastModified: aws.Time(time.Unix(entry.Attributes.Mtime, 0)),
+				Size:         aws.Int64(int64(filer2.TotalSize(entry.Chunks))),
+				ETag:         aws.String("\"" + filer2.ETag(entry.Chunks) + "\""),
+			})
+		}
+	}
+
 	return
 }
diff --git a/weed/s3api/filer_util.go b/weed/s3api/filer_util.go
index a44305505..f0949389c 100644
--- a/weed/s3api/filer_util.go
+++ b/weed/s3api/filer_util.go
@@ -34,7 +34,7 @@ func (s3a *S3ApiServer) mkdir(parentDirectoryPath string, dirName string, fn fun
 			Entry:     entry,
 		}
 
-		glog.V(1).Infof("create bucket: %v", request)
+		glog.V(1).Infof("mkdir: %v", request)
 		if _, err := client.CreateEntry(context.Background(), request); err != nil {
 			return fmt.Errorf("mkdir %s/%s: %v", parentDirectoryPath, dirName, err)
 		}
@@ -43,12 +43,46 @@ func (s3a *S3ApiServer) mkdir(parentDirectoryPath string, dirName string, fn fun
 	})
 }
 
-func (s3a *S3ApiServer) list(parentDirectoryPath string) (entries []*filer_pb.Entry, err error) {
+func (s3a *S3ApiServer) mkFile(parentDirectoryPath string, fileName string, chunks []*filer_pb.FileChunk) error {
+	return s3a.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
+
+		entry := &filer_pb.Entry{
+			Name:        fileName,
+			IsDirectory: false,
+			Attributes: &filer_pb.FuseAttributes{
+				Mtime:    time.Now().Unix(),
+				Crtime:   time.Now().Unix(),
+				FileMode: uint32(0770),
+				Uid:      OS_UID,
+				Gid:      OS_GID,
+			},
+			Chunks: chunks,
+		}
+
+		request := &filer_pb.CreateEntryRequest{
+			Directory: parentDirectoryPath,
+			Entry:     entry,
+		}
+
+		glog.V(1).Infof("create file: %s/%s", parentDirectoryPath, fileName)
+		if _, err := client.CreateEntry(context.Background(), request); err != nil {
+			return fmt.Errorf("create file %s/%s: %v", parentDirectoryPath, fileName, err)
+		}
+
+		return nil
+	})
+}
+
+func (s3a *S3ApiServer) list(parentDirectoryPath, prefix, startFrom string, inclusive bool, limit int) (entries []*filer_pb.Entry, err error) {
 
 	err = s3a.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
 		request := &filer_pb.ListEntriesRequest{
-			Directory: s3a.option.BucketsPath,
+			Directory:          s3a.option.BucketsPath,
+			Prefix:             prefix,
+			StartFromFileName:  startFrom,
+			InclusiveStartFrom: inclusive,
+			Limit:              uint32(limit),
 		}
 
 		glog.V(4).Infof("read directory: %v", request)
@@ -101,10 +135,10 @@ func (s3a *S3ApiServer) exists(parentDirectoryPath string, entryName string, isD
 			Name:      entryName,
 		}
 
-		glog.V(1).Infof("delete entry %v/%v: %v", parentDirectoryPath, entryName, request)
+		glog.V(1).Infof("exists entry %v/%v: %v", parentDirectoryPath, entryName, request)
 		resp, err := client.LookupDirectoryEntry(ctx, request)
 		if err != nil {
-			return fmt.Errorf("delete entry %s/%s: %v", parentDirectoryPath, entryName, err)
+			return fmt.Errorf("exists entry %s/%s: %v", parentDirectoryPath, entryName, err)
 		}
 
 		exists = resp.Entry.IsDirectory == isDirectory
diff --git a/weed/s3api/s3api_bucket_handlers.go b/weed/s3api/s3api_bucket_handlers.go
index 5257e67b4..df9abd451 100644
--- a/weed/s3api/s3api_bucket_handlers.go
+++ b/weed/s3api/s3api_bucket_handlers.go
@@ -21,7 +21,7 @@ func (s3a *S3ApiServer) ListBucketsHandler(w http.ResponseWriter, r *http.Reques
 
 	var response ListAllMyBucketsResponse
 
-	entries, err := s3a.list(s3a.option.BucketsPath)
+	entries, err := s3a.list(s3a.option.BucketsPath, "", "", false, 0)
 
 	if err != nil {
 		writeErrorResponse(w, ErrInternalError, r.URL)
diff --git a/weed/s3api/s3api_object_multipart_handlers.go b/weed/s3api/s3api_object_multipart_handlers.go
index 62b702a39..042736856 100644
--- a/weed/s3api/s3api_object_multipart_handlers.go
+++ b/weed/s3api/s3api_object_multipart_handlers.go
@@ -143,6 +143,8 @@ func (s3a *S3ApiServer) ListMultipartUploadsHandler(w http.ResponseWriter, r *ht
 		return
 	}
 
+	// TODO handle encodingType
+
 	writeSuccessResponseXML(w, encodeResponse(response))
 }
 
diff --git a/weed/s3api/s3api_objects_list_handlers.go b/weed/s3api/s3api_objects_list_handlers.go
index 721982d0f..e104b4c9e 100644
--- a/weed/s3api/s3api_objects_list_handlers.go
+++ b/weed/s3api/s3api_objects_list_handlers.go
@@ -11,10 +11,10 @@ import (
 
 	"github.com/aws/aws-sdk-go/aws"
 	"github.com/aws/aws-sdk-go/service/s3"
-	"github.com/chrislusf/seaweedfs/weed/filer2"
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
 	"github.com/gorilla/mux"
+	"github.com/chrislusf/seaweedfs/weed/filer2"
 )
 
 const (
@@ -126,7 +126,7 @@ func (s3a *S3ApiServer) listFilerEntries(bucket, originalPrefix string, maxKeys
 				contents = append(contents, &s3.Object{
 					Key:          aws.String(fmt.Sprintf("%s%s", dir, entry.Name)),
 					LastModified: aws.Time(time.Unix(entry.Attributes.Mtime, 0)),
-					ETag:         aws.String("\"2345sgfwetrewrt\""), // TODO add etag
+					ETag:         aws.String("\"" + filer2.ETag(entry.Chunks) + "\""),
 					Size:         aws.Int64(int64(filer2.TotalSize(entry.Chunks))),
 					Owner: &s3.Owner{
 						ID:          aws.String("bcaf161ca5fb16fd081034f"),
diff --git a/weed/server/filer_server_handlers_read.go b/weed/server/filer_server_handlers_read.go
index e17cd776d..eaa8015a6 100644
--- a/weed/server/filer_server_handlers_read.go
+++ b/weed/server/filer_server_handlers_read.go
@@ -119,6 +119,7 @@ func (fs *FilerServer) handleMultipleChunks(w http.ResponseWriter, r *http.Reque
 	if mimeType != "" {
 		w.Header().Set("Content-Type", mimeType)
 	}
+	setEtag(w, filer2.ETag(entry.Chunks))
 
 	totalSize := int64(filer2.TotalSize(entry.Chunks))
 
diff --git a/weed/server/filer_server_handlers_write.go b/weed/server/filer_server_handlers_write.go
index 8a19f3fdb..2f9351fa1 100644
--- a/weed/server/filer_server_handlers_write.go
+++ b/weed/server/filer_server_handlers_write.go
@@ -150,6 +150,7 @@ func (fs *FilerServer) PostHandler(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	defer resp.Body.Close()
+	etag := resp.Header.Get("ETag")
 	resp_body, ra_err := ioutil.ReadAll(resp.Body)
 	if ra_err != nil {
 		glog.V(0).Infoln("failing to upload to volume server", r.RequestURI, ra_err.Error())
@@ -202,6 +203,7 @@ func (fs *FilerServer) PostHandler(w http.ResponseWriter, r *http.Request) {
 			FileId: fileId,
 			Size:   uint64(ret.Size),
 			Mtime:  time.Now().UnixNano(),
+			ETag:   etag,
 		}},
 	}
 	if db_err := fs.filer.CreateEntry(entry); db_err != nil {
diff --git a/weed/server/volume_server_handlers_read.go b/weed/server/volume_server_handlers_read.go
index 54f08971f..4da13883e 100644
--- a/weed/server/volume_server_handlers_read.go
+++ b/weed/server/volume_server_handlers_read.go
@@ -88,12 +88,11 @@ func (vs *VolumeServer) GetOrHeadHandler(w http.ResponseWriter, r *http.Request)
 			}
 		}
 	}
-	etag := n.Etag()
-	if inm := r.Header.Get("If-None-Match"); inm == etag {
+	if inm := r.Header.Get("If-None-Match"); inm == "\""+n.Etag()+"\"" {
 		w.WriteHeader(http.StatusNotModified)
 		return
 	}
-	w.Header().Set("Etag", etag)
+	setEtag(w, n.Etag())
 
 	if n.HasPairs() {
 		pairMap := make(map[string]string)
diff --git a/weed/server/volume_server_handlers_write.go b/weed/server/volume_server_handlers_write.go
index d32958339..a0b142dea 100644
--- a/weed/server/volume_server_handlers_write.go
+++ b/weed/server/volume_server_handlers_write.go
@@ -44,8 +44,7 @@ func (vs *VolumeServer) PostHandler(w http.ResponseWriter, r *http.Request) {
 		ret.Name = string(needle.Name)
 	}
 	ret.Size = size
-	etag := needle.Etag()
-	w.Header().Set("Etag", etag)
+	setEtag(w, needle.Etag())
 	writeJsonQuiet(w, r, httpStatus, ret)
 }
 
@@ -173,3 +172,9 @@ func (vs *VolumeServer) batchDeleteHandler(w http.ResponseWriter, r *http.Reques
 
 	writeJsonQuiet(w, r, http.StatusAccepted, ret)
 }
+
+func setEtag(w http.ResponseWriter, etag string) {
+	if etag != "" {
+		w.Header().Set("ETag", "\""+etag+"\"")
+	}
+}
diff --git a/weed/storage/crc.go b/weed/storage/crc.go
index 494937784..e31e0f815 100644
--- a/weed/storage/crc.go
+++ b/weed/storage/crc.go
@@ -26,5 +26,5 @@ func (c CRC) Value() uint32 {
 func (n *Needle) Etag() string {
 	bits := make([]byte, 4)
 	util.Uint32toBytes(bits, uint32(n.Checksum))
-	return fmt.Sprintf("\"%x\"", bits)
+	return fmt.Sprintf("%x", bits)
 }