diff --git a/weed/operation/upload_content.go b/weed/operation/upload_content.go
index 5c02c77ac..4ce3e6149 100644
--- a/weed/operation/upload_content.go
+++ b/weed/operation/upload_content.go
@@ -194,11 +194,12 @@ func NewUploaderWithHttpClient(httpClient HTTPClient) *Uploader {
 	}
 }
 
-func (uploader *Uploader) uploadWithRetryData(assignFn func() (fileId string, host string, auth security.EncodedJwt, err error), uploadOption *UploadOption, data []byte) (fileId string, uploadResult *UploadResult, err error) {
+func (uploader *Uploader) uploadWithRetryData(assignFn func() (fileId string, host string, auth security.EncodedJwt, fsync bool, err error), uploadOption *UploadOption, data []byte) (fileId string, uploadResult *UploadResult, err error) {
 	doUploadFunc := func() error {
 		var host string
 		var auth security.EncodedJwt
-		fileId, host, auth, err = assignFn()
+		var fsync bool
+		fileId, host, auth, fsync, err = assignFn()
 		if err != nil {
 			return err
 		}
@@ -208,6 +209,9 @@ func (uploader *Uploader) uploadWithRetryData(assignFn func() (fileId string, ho
 			genUrl = func(host, fileId string) string { return fmt.Sprintf("http://%s/%s", host, fileId) }
 		}
 		uploadOption.UploadUrl = genUrl(host, fileId)
+		if fsync {
+			uploadOption.UploadUrl = util_http.AppendQueryParameter(uploadOption.UploadUrl, "fsync", "true")
+		}
 		uploadOption.Jwt = auth
 		if util_http.IsProxyChunkUrl(uploadOption.UploadUrl) {
 			// The request addresses the filer, which authorizes it and mints the
@@ -263,7 +267,7 @@ func (uploader *Uploader) UploadWithRetry(filerClient filer_pb.FilerClient, assi
 		uploadOption.Md5 = base64.StdEncoding.EncodeToString(digest[:])
 	}
 
-	fileId, uploadResult, err = uploader.uploadWithRetryData(func() (fileId string, host string, auth security.EncodedJwt, err error) {
+	fileId, uploadResult, err = uploader.uploadWithRetryData(func() (fileId string, host string, auth security.EncodedJwt, fsync bool, err error) {
 		// grpc assign volume
 		if grpcAssignErr := filerClient.WithFilerClient(false, func(client filer_pb.SeaweedFilerClient) error {
 			assignCtx, assignCancel := context.WithTimeout(context.Background(), assignVolumeTimeout)
@@ -278,6 +282,7 @@ func (uploader *Uploader) UploadWithRetry(filerClient filer_pb.FilerClient, assi
 			}
 
 			fileId, auth = resp.FileId, security.EncodedJwt(resp.Auth)
+			fsync = resp.Fsync
 			loc := resp.Location
 			host = filerClient.AdjustedUrl(loc)
 
diff --git a/weed/operation/upload_content_test.go b/weed/operation/upload_content_test.go
index 8923d33e5..ebbfb722f 100644
--- a/weed/operation/upload_content_test.go
+++ b/weed/operation/upload_content_test.go
@@ -95,12 +95,12 @@ func TestUploadWithRetryDataReassignsOnVolumeSizeExceeded(t *testing.T) {
 	uploader := newUploader(httpClient)
 
 	assignCalls := 0
-	fileID, uploadResult, err := uploader.uploadWithRetryData(func() (string, string, security.EncodedJwt, error) {
+	fileID, uploadResult, err := uploader.uploadWithRetryData(func() (string, string, security.EncodedJwt, bool, error) {
 		assignCalls++
 		if assignCalls == 1 {
-			return "1,first", "volume-a", "", nil
+			return "1,first", "volume-a", "", false, nil
 		}
-		return "2,second", "volume-b", "", nil
+		return "2,second", "volume-b", "", false, nil
 	}, &UploadOption{Filename: "test.bin"}, []byte("abc"))
 
 	if err != nil {
@@ -143,12 +143,12 @@ func TestUploadWithRetryDataReassignsOnReplicaWriteFailure(t *testing.T) {
 	uploader := newUploader(httpClient)
 
 	assignCalls := 0
-	fileID, uploadResult, err := uploader.uploadWithRetryData(func() (string, string, security.EncodedJwt, error) {
+	fileID, uploadResult, err := uploader.uploadWithRetryData(func() (string, string, security.EncodedJwt, bool, error) {
 		assignCalls++
 		if assignCalls == 1 {
-			return "1,first", "volume-a", "", nil
+			return "1,first", "volume-a", "", false, nil
 		}
-		return "2,second", "volume-b", "", nil
+		return "2,second", "volume-b", "", false, nil
 	}, &UploadOption{Filename: "test.bin"}, []byte("abc"))
 
 	if err != nil {
@@ -199,6 +199,64 @@ func (c *bodyCapturingHTTPClient) Do(req *http.Request) (*http.Response, error)
 	}, nil
 }
 
+type fsyncAssignClient struct {
+	filer_pb.SeaweedFilerClient
+	response *filer_pb.AssignVolumeResponse
+}
+
+func (c *fsyncAssignClient) AssignVolume(context.Context, *filer_pb.AssignVolumeRequest, ...grpc.CallOption) (*filer_pb.AssignVolumeResponse, error) {
+	return c.response, nil
+}
+
+func (c *fsyncAssignClient) WithFilerClient(_ bool, fn func(filer_pb.SeaweedFilerClient) error) error {
+	return fn(c)
+}
+func (c *fsyncAssignClient) AdjustedUrl(loc *filer_pb.Location) string { return loc.GetUrl() }
+func (c *fsyncAssignClient) GetDataCenter() string                     { return "" }
+
+func TestUploadWithRetryAppendsFsyncWhenAssigned(t *testing.T) {
+	for _, tc := range []struct {
+		name  string
+		proxy bool
+	}{
+		{name: "direct"},
+		{name: "filer proxy", proxy: true},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			const fileID = "1,0123456789"
+			server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+				if gotFsync := r.URL.Query().Get("fsync"); gotFsync != "true" {
+					t.Errorf("upload fsync = %q, want true when assignment requires fsync", gotFsync)
+				}
+				if tc.proxy {
+					if got := r.URL.Query().Get("proxyChunkId"); got != fileID {
+						t.Errorf("proxyChunkId = %q, want %q", got, fileID)
+					}
+				}
+				w.WriteHeader(http.StatusCreated)
+				_, _ = io.WriteString(w, `{"size":3}`)
+			}))
+			defer server.Close()
+
+			host := strings.TrimPrefix(server.URL, "http://")
+			client := &fsyncAssignClient{response: &filer_pb.AssignVolumeResponse{
+				FileId:   fileID,
+				Location: &filer_pb.Location{Url: host},
+				Fsync:    true,
+			}}
+			option := &UploadOption{}
+			if tc.proxy {
+				option.GenUploadUrl = GenUploadUrlProxy(host)
+			}
+			_, _, err, _ := newUploader(server.Client()).UploadWithRetry(client,
+				&filer_pb.AssignVolumeRequest{Path: "/bucket/object"}, option, strings.NewReader("abc"))
+			if err != nil {
+				t.Fatalf("upload failed: %v", err)
+			}
+		})
+	}
+}
+
 // hangingAssignSeaweedClient is a SeaweedFilerClient whose AssignVolume blocks
 // until its context is done, so a test can prove UploadWithRetry bounds the RPC.
 type hangingAssignSeaweedClient struct {