// as well as common modtime, if modtime is not possible
		// verify if it has common "etag" at least.
		if onlineMeta[i].IsValid() && onlineMeta[i].Erasure.Equal(fi.Erasure) {
			ok := onlineMeta[i].ModTime.Equal(modTime)
			if modTime.IsZero() || modTime.Equal(timeSentinel) {
				ok = etag != "" && etag == fi.Metadata["etag"]
			}
			if ok {
				continue
			}

type PartTooBig struct{}

func (e PartTooBig) Error() string {
	return "Part size bigger than the allowed limit"
}

// InvalidETag error returned when the etag has changed on disk
type InvalidETag struct{}

func (e InvalidETag) Error() string {
	return "etag of the object has changed"
}

// BackendDown is returned for network errors
type BackendDown struct {
	Err string
}

		MTime:        srcObjInfo.ModTime,
		PreserveETag: srcObjInfo.ETag,
		UserDefined:  srcObjInfo.UserDefined,
	}
	if r.Target.Type == BatchJobReplicateResourceS3 || r.Source.Type == BatchJobReplicateResourceS3 {
		opts.VersionID = ""
	}
	if crypto.S3.IsEncrypted(srcObjInfo.UserDefined) {
		opts.ServerSideEncryption = encrypt.NewSSE()
	}
	slc := strings.Split(srcObjInfo.ETag, "-")
	if len(slc) == 2 {