XTLS/Xray-core · error

failed to transport all UDP request

Error message

failed to transport all UDP request

What it means

Error "failed to transport all UDP request" thrown in XTLS/Xray-core.

Source

Thrown at proxy/hysteria/client.go:139

	}

	if target.Network == net.Network_UDP {
		iConn := stat.TryUnwrapStatsConn(conn)
		_, ok := iConn.(*hysteria.InterConn)
		if !ok {
			return errors.New("udp requires hysteria udp transport")
		}

		requestDone := func() error {
			defer timer.SetTimeout(sessionPolicy.Timeouts.DownlinkOnly)

			writer := &UDPWriter{
				writer: conn,
				addr:   target.NetAddr(),
			}

			if err := buf.Copy(link.Reader, writer, buf.UpdateActivity(timer)); err != nil {
				return errors.New("failed to transport all UDP request").Base(err)
			}

			return nil
		}

		responseDone := func() error {
			defer timer.SetTimeout(sessionPolicy.Timeouts.UplinkOnly)

			reader := &UDPReader{
				reader: conn,
				df:     &Defragger{},
			}

			if err := buf.Copy(reader, link.Writer, buf.UpdateActivity(timer)); err != nil {
				return errors.New("failed to transport all UDP response").Base(err)
			}

			return nil

View on GitHub (pinned to 7d214f8b09)

When it happens

Trigger: Thrown at proxy/hysteria/client.go:139 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of XTLS/Xray-core@7d214f8b09 (2026-08-15). Data as JSON: /api/errors/fae04ad8d9b6db87. Report an issue: GitHub.